I ordered these by accident.
A little place in Tucson with six tables, a paper menu, and a waiter who was clearly busy, and I pointed at the wrong line.
What arrived was a vegetable taco, and I remember being mildly annoyed about it.
Then I ate one.
The sweet potato had gone soft and dense and slightly sweet, the cauliflower was browned hard at the florets and tasted almost nutty, and there was a smoky orange sauce over the top holding the whole thing together.
I asked what was in the sauce and the waiter said chipotle and shrugged.
That shrug cost me four attempts at home.
What I eventually worked out is that this taco isn't a substitute for anything.
The two vegetables are doing opposite jobs on purpose.
Sweet potato brings the soft, dense, slightly sweet bite that a filling needs to feel like a meal.
Cauliflower brings the browned edges and the savory depth.
The chipotle sauce brings smoke and acid, which is the part that makes your brain file it under taco instead of roasted vegetables in a tortilla.
Both vegetables roast on one pan at the same temperature, the sauce is five things in a blender, and the onions pickle while the oven does the work.
Fifty minutes, and nobody at my table asks where the meat is.
Why This Combination Works
Two vegetables, two completely different jobs. That's the reason this taco holds up and a pan of plain roasted vegetables in a tortilla doesn't.
Sweet potato is dense and holds moisture, so a cube of it eats soft and substantial, closer to the mouthfeel of a braised filling than to a vegetable.
Cauliflower does the opposite. It's mostly water, it dries out at the edges, and those edges go deep brown and taste nutty and savory.
Put them together and you get softness and browned crunch in the same bite.
The sauce is the third leg, and it isn't optional.
Sweet potato without acid tastes flat and slightly cloying in a tortilla.
The chipotle sauce cuts through it with lime and smoke, and the pickled onions come in sharp on top of that.
Take either one away and you'll taste the gap immediately.
Ingredients You'll Need
Three components, and each one is short. Nothing here needs a special trip beyond a can of chipotles in adobo.
For the Roasted Vegetables
- Sweet potatoes (1 ¼ pounds). Peeled and cut into ½ inch cubes. The size is not a suggestion, it's what makes the shared pan work.
- Cauliflower (1 medium head). Cut into small florets, a bit bigger than the sweet potato cubes.
- Olive oil (3 tablespoons). Split across both vegetables.
- Chili powder (2 teaspoons). The base warmth.
- Ground cumin (1 ½ teaspoons). The single spice both competitors agree on, and for good reason.
- Smoked paprika (1 teaspoon). It doubles down on the smoke in the sauce.
- Kosher salt (1 teaspoon).
For the Chipotle Sauce
- Sour cream (¾ cup). Full fat. Low fat splits and goes thin.
- Chipotle peppers in adobo (1 to 2), plus 1 teaspoon of the adobo. One pepper is warm, two is properly spicy.
- Lime juice (2 tablespoons). Fresh. This is the acid the whole plate leans on.
- Garlic (1 small clove). Raw, blended in.
- Maple syrup (1 teaspoon). A trick worth stealing. It rounds off the harsh edge of the adobo without making the sauce sweet.
- Kosher salt (¼ teaspoon).
For the Pickled Onions and Assembly
- Red onion (1 small). Sliced as thin as you can manage.
- White vinegar (½ cup), sugar (2 teaspoons), salt (½ teaspoon). The whole pickle.
- Corn tortillas (12). See below, this matters more than you'd think.
- Cilantro and lime wedges. To finish.
Can You Roast Cauliflower and Sweet Potato Together
Yes, and the trick is cut size, not timing. This is the question I see asked most about this recipe and the answer is simple once you see it.
Sweet potato is dense and slow. Cauliflower is airy and fast.
So you cut the sweet potato small, ½ inch cubes, and leave the cauliflower florets a little larger, roughly 1 ½ inches across.
Cut that way, they finish within a couple of minutes of each other at 425°F.
Two more rules and you're done.
Single layer with space. A crowded pan steams, and steamed cauliflower is a genuinely unpleasant thing. Use two pans if one looks tight.
Stir once at 20 minutes. Turn everything so the pale faces come down onto the metal, then give it another 10 to 12 minutes.
You want the cauliflower florets browned at the tips and the sweet potato cubes soft with a few dark corners.
The Chipotle Sauce
Five ingredients and a blender, ninety seconds. I've made the fancy version with roasted garlic and almonds and it's excellent, but this one goes on a weeknight taco and it hits the same note.
Everything into a blender or a small food processor: sour cream, chipotle and adobo, lime juice, garlic, maple, salt.
Blend until it's smooth and a uniform pale orange with no visible flecks of pepper skin.
Taste it. It should be smoky first, tangy second, and warm at the back.
Dialing the heat: start with one chipotle. You can add a second and reblend in ten seconds, but you cannot take it out.
No blender? Mince the chipotle to a paste on the board with the flat of your knife and stir everything together. The texture is slightly rustic and it tastes the same.
The sauce should pour off a spoon in a thick ribbon. If it's stiff, thin it with a teaspoon of water at a time.
Quick Pickled Red Onions
These pickle in the time the oven takes, so make them first.
Slice the onion as thinly as you can and pack it into a jar or a small bowl.
Warm the vinegar with the sugar and salt just until they dissolve, then pour it over the onion.
Press the slices down so they're submerged and leave them on the counter.
They go bright pink and lose their raw bite in about 30 minutes.
They keep 2 weeks in the fridge and I always make a double jar, because they end up on everything.
How to Assemble the Tacos
Step 1: Char the Tortillas
Straight on a gas burner over a medium flame, about 20 seconds per side, until they're blistered and blackened in spots.
No gas? A dry cast iron skillet over medium high heat does the same job in 30 seconds a side.
Step 2: Stack Them Warm
Pile the charred tortillas in a clean kitchen towel and fold it over.
They steam each other soft and pliable while you finish, which is what keeps them from cracking when you fold them.
Step 3: Build
Vegetables first, a generous spoonful across the middle of the tortilla.
Pickled onions next.
Then the chipotle sauce over the top, cilantro, and a lime wedge on the side of the plate.
Sauce goes on last, not on the tortilla first. On the bottom it soaks in and the tortilla goes soft on you.
Getting the Tortillas Right
Corn, not flour. This is one of the few places I'll be stubborn.
The filling here is soft and sweet, and a flour tortilla is soft and mild, so the whole taco turns into one texture and one flavor.
Corn brings toasted, slightly bitter, distinctly savory, and that's what the sweet potato is asking for.
Use two tortillas per taco if yours are thin. That's how they're served everywhere they're served well, and it stops the blowout.
Fair warning: a cold tortilla cracks. Every single time. Char them or at least warm them, no exceptions.
Variations
- Dairy free. Swap the sour cream for ¾ cup of raw cashews soaked in hot water for 20 minutes and blended with ¼ cup of water, or use a plain plant based sour cream.
- Add black beans. A drained can, warmed with a little cumin, stretches this to six people.
- Add poblano. One or two, sliced and roasted on the pan with the vegetables. They bring a green, grassy note.
- Milder. Use a teaspoon of ancho chili powder in the sauce instead of the chipotle. You keep the smoke and lose most of the heat.
- Add crunch. A handful of shredded red cabbage tossed with lime juice, right under the sauce.
- Make it a bowl. Everything over cilantro rice, sauce spooned across the top.
What to Serve With Them
- Cilantro lime rice. The standard, and it soaks up the extra sauce.
- Black beans. Simmered with a bay leaf and a little cumin.
- Cabbage slaw. Shredded cabbage, lime, salt, a little oil. Ten minutes and it lightens the whole plate.
- Elote style corn. If you're already at the grill.
- A lime spritz. Lime, soda water, ice. It's the right drink for this.
Make Ahead and Storage
This is really three separate components, which makes it a great Sunday project.
- Roasted vegetables. 4 days in the fridge. Reheat spread on a sheet pan at 425°F for 8 minutes so the edges crisp again. A microwave turns them to mush.
- Chipotle sauce. 1 week in a sealed jar. It thickens as it sits, so loosen it with a little lime juice.
- Pickled onions. 2 weeks, and they get better after the first day.
- Assembled tacos. Don't. Build them at the table, or the tortillas go soggy within minutes.
- Freezer. The roasted vegetables freeze for 2 months, though the cauliflower loses its edge. The sauce doesn't freeze well at all.
Recipe
Roasted Sweet Potato and Cauliflower Tacos with Chipotle Sauce
Ingredients
Roasted Vegetables
- 1 ¼ pounds sweet potatoes peeled and cut into ½ inch cubes
- 1 medium head cauliflower cut into small florets, about 1 ½ inches
- 3 tablespoons olive oil
- 2 teaspoons chili powder
- 1 ½ teaspoons ground cumin
- 1 teaspoon smoked paprika
- 1 teaspoon kosher salt
Chipotle Sauce
- ¾ cup sour cream full fat
- 1 to 2 chipotle peppers in adobo plus 1 teaspoon of the adobo sauce
- 2 tablespoons lime juice fresh
- 1 small clove garlic
- 1 teaspoon maple syrup
- ¼ teaspoon kosher salt
Quick Pickled Onions
- 1 small red onion very thinly sliced
- ½ cup white vinegar
- 2 teaspoons sugar
- ½ teaspoon kosher salt
To Serve
- 12 corn tortillas
- ½ cup fresh cilantro chopped
- 1 lime cut into wedges
Instructions
Pickle the Onions
- Pack the thinly sliced red onion into a jar or small bowl.
- Warm the vinegar with the sugar and salt just until they dissolve, pour it over the onion, and press the slices under the liquid. Leave on the counter at least 30 minutes.
Roast the Vegetables
- Heat the oven to 425 degrees F.
- Toss the sweet potato cubes and cauliflower florets with the olive oil, chili powder, cumin, smoked paprika, and salt until evenly coated.
- Spread in a single layer on a large unlined sheet pan with space between the pieces. Use two pans rather than crowding one.
- Roast 20 minutes, stir and turn everything so the pale faces come down onto the metal, then roast 10 to 12 minutes more, until the cauliflower tips are browned and the sweet potato is soft with dark corners.
Make the Sauce
- Blend the sour cream, chipotle peppers and adobo, lime juice, garlic, maple syrup, and salt until completely smooth and pale orange. Start with one chipotle, taste, and add the second if you want more heat.
- Thin with a teaspoon of water at a time if the sauce is too stiff to ribbon off a spoon.
Assemble
- Char the corn tortillas directly over a medium gas flame for about 20 seconds per side, or in a dry cast iron skillet over medium high heat for 30 seconds per side, until blistered in spots.
- Stack the charred tortillas in a clean kitchen towel and fold it over so they steam soft while you finish.
- Fill each tortilla with the roasted vegetables, add pickled onions, spoon the chipotle sauce over the top, and finish with cilantro. Serve with lime wedges.
Notes
- Cut size is what lets them share a pan: ½ inch sweet potato cubes against 1 ½ inch cauliflower florets finish within a couple of minutes of each other.
- Do not crowd the pan: Crowded vegetables steam. Two pans beat one full one.
- Sauce last: Spoon it over the filling, never onto the bare tortilla, or the tortilla softens.
- Heat control: One chipotle is warm, two is properly spicy. Add the second after tasting.
- Dairy free: Blend ¾ cup cashews soaked 20 minutes in hot water with ¼ cup water in place of the sour cream.
- Storage: Vegetables 4 days, sauce 1 week, onions 2 weeks, all stored separately. Reheat the vegetables on a sheet pan, not in the microwave.
