There's a taqueria two blocks from my old apartment that ran one soup and never changed it.
Thin red broth, smoky enough to make you sit up, with cubes of something orange floating in it.
I assumed squash for about a year.
It was sweet potato, and the cook told me so while she was scooping strips out of a pot of oil behind the counter.
She handed the bowl over with the strips in a separate paper cone.
That detail is the whole reason I still make this at home.
The strips go in at the table, not in the pot.
I make a batch of this every couple of weeks from October on, usually on a Sunday when I've got twenty minutes to stand at the stove and fry a stack of tortillas.
My wife eats it for lunch three days running and never complains, which for her is a rave review.
It's brothy, not thick.
You can see through it.
The sweet potato stays in soft cubes you can actually bite, the chipotle does the heavy work on flavor, and a hard squeeze of lime at the end keeps the whole pot from tasting flat and sweet.
Under an hour, one pot, and the only fussy part is three minutes of frying.
I promise the strips are worth those three minutes.
This Is a Brothy Soup, Not a Puree
Nothing in this recipe gets blended. Search sweet potato soup and you'll get a wall of smooth orange purees, which is a fine thing to eat but is not this.
This bowl is thin.
The broth is a see-through tomato red, loose enough to run off the spoon, and the sweet potato sits in it as distinct ½ inch cubes.
It's also not a chili, which is the other thing people expect from this ingredient list.
No thickener, no masa, no cornstarch.
Fair warning: if you cook it too long the cubes surrender and the broth turns cloudy, and at that point you have made a very nice sweet potato chowder instead. Still good. Not this.
Ingredients You Need
- Sweet potatoes (1 ½ pounds). Peeled and cut into ½ inch cubes. Cut them all the same size or half will be mush before the other half is tender.
- Chipotle peppers in adobo (2, minced, plus 1 teaspoon sauce). The most important can in this recipe. Smoke and heat in one move, and the adobo sauce carries as much flavor as the peppers.
- Fire roasted crushed tomatoes (28 ounce can). Fire roasted, not plain. The char is doing real work in a soup this thin.
- Chicken or vegetable broth (6 cups). Six cups sounds like a lot. It's what makes this brothy instead of stewy.
- Chili powder (1 tablespoon) and ground cumin (2 teaspoons). Bloomed in oil, never stirred into liquid.
- Smoked paprika (1 teaspoon). Backs up the chipotle without adding heat.
- Jalapeno (1, seeded and minced). Fresh green heat, a different note from the chipotle's dried smoke.
- Yellow onion (1) and garlic (4 cloves). The base. Nothing exotic.
- Tomato paste (2 tablespoons). Cooked in with the spices for a minute so it darkens.
- Black beans (15 ounce can) and frozen corn (1 ½ cups). Both go in near the end. The corn should still pop.
- Corn tortillas (6) and neutral oil (½ cup). For the strips. Corn only, flour tortillas turn to leather.
- Lime (1, juiced, plus wedges). Non negotiable. Sweet potato plus tomato needs acid or it reads like sweetened soup.
Toppings are up to you, and I'll get to what each one is for further down.
Bloom the Spices First
Dry chili powder dumped into broth tastes like dust. Thirty seconds in hot oil and the same spoonful tastes like a completely different spice.
Push the softened onion to the side of the pot, add the chili powder, cumin, smoked paprika and tomato paste into the bare oil, and stir them for 45 to 60 seconds.
You'll see the paste go from bright red to brick.
You'll smell it before you see it.
Worth the extra step? Every time.
How to Make Sweet Potato Tortilla Soup
Step 1: Soften the Onion, Garlic and Jalapeno
Heat 2 tablespoons olive oil in a large pot over medium heat.
Add the diced onion and minced jalapeno with a pinch of salt and cook 5 to 6 minutes, until the onion is translucent and floppy.
Garlic goes in for the last 30 seconds only.
Step 2: Bloom the Chili Powder, Cumin and Chipotle
Clear a space in the pot and add the tomato paste, chili powder, cumin, smoked paprika and the minced chipotle peppers with their adobo sauce.
Stir that mixture in the oil for a full minute.
Then stir it through the onions.
Step 3: Add Tomatoes and Broth
Pour in the crushed fire roasted tomatoes and scrape the bottom of the pot.
Add the 6 cups of broth and 1 ½ teaspoons kosher salt, and bring it up to a steady simmer.
Step 4: Simmer the Sweet Potato Until Just Tender
Add the cubed sweet potato only once the liquid is simmering.
Cook 12 to 15 minutes, uncovered, and start testing at 12.
You want a knife to slide in with a little resistance still there.
Step 5: Add Corn and Beans, Then Lime Off the Heat
Stir in the drained black beans and the frozen corn and give it 3 minutes, just long enough to heat through.
Kill the heat.
Now add the lime juice, off the burner, and taste for salt.
Pro tip: lime juice added to a boiling pot goes bitter and dull within a few minutes. Off the heat it stays bright.
The Tortilla Strips Are the Recipe
A tortilla soup without crisp strips is just a vegetable soup with a Mexican accent. This is the part people skip and then wonder why theirs tastes ordinary.
Stack 6 corn tortillas, cut the stack in half, then cut across into ¼ inch ribbons.
Heat ½ cup of neutral oil in a small skillet until a test strip sizzles hard on contact.
Fry in two or three batches, never all at once, for 60 to 90 seconds until they stop bubbling and go pale gold.
Lift them onto paper towel and salt them immediately, while the oil is still wet on the surface.
Salt them cold and it just falls off.
Oven method: toss the strips with 1 tablespoon oil, spread them on a sheet pan and bake at 400°F for 10 to 12 minutes, tossing once. Less shattery, still good.
Store bought chips work in a pinch and I've used them plenty, but they're thicker and they go soft faster.
Keeping the Sweet Potato Cubes Intact
Mushy cubes are the number one thing that goes wrong here. Three rules fix it.
- Cut at ½ inch, uniformly. Big ragged chunks and small slivers in one pot means you cook to the average and nothing is right.
- Add them to simmering liquid, not cold. Cubes that heat up slowly from cold have longer to break down at the surface.
- Pull the pot early. They keep cooking in the hot broth for another five minutes after the burner is off, so stop while there's still a little bite.
NEVER stir it hard once the potato is in.
A gentle stir every few minutes is plenty, and aggressive stirring is what knocks the corners off and clouds your broth.
Toppings, and What Each One Is Actually For
- Diced avocado. Fat. This soup has almost none, and a few cubes of avocado give it body without thickening it.
- Crumbled cotija. Salt and a dry crumble. Queso fresco if you want it milder, and honestly a sharp feta is a fine stand in.
- Thin sliced red onion. Raw bite against the soft cooked vegetables.
- Chopped cilantro. Green and grassy, which the pot has none of otherwise.
- A lime wedge on the rim. A second hit of acid at the table, because the acid from step five fades as the bowl sits.
- Sour cream. If you want it, add a small spoonful. It mutes the smoke, so I usually leave it out.
Who doesn't love a bowl you get to build yourself?
Make It With Chicken
This version takes chicken beautifully and it's how I make it when I've got a rotisserie bird in the fridge.
Shred 2 cups of cooked chicken and stir it in with the beans and corn in step five.
Use chicken broth instead of vegetable, and cut the salt to 1 teaspoon to start since the bird is already seasoned.
Nothing else changes.
Storage and Reheating
- The soup. Airtight in the fridge for 4 days. Day two is better than day one, the chipotle settles into the broth.
- The strips. A separate container at room temperature, loosely covered, for 2 days. In the fridge they go limp, and in the soup they're gone in an hour.
- Reheating. Gently on the stove over medium low. A hard boil finishes off whatever structure the sweet potato had left.
- Freezing. Up to 3 months. Beans and corn come through fine, the sweet potato softens a little, and the texture is still good.
- Toppings. Avocado never survives storage. Cut it fresh or skip it.
If the broth has tightened up in the fridge, and it will a little, thin it with a splash of broth or water as it warms.
A fresh squeeze of lime over the reheated bowl brings the whole thing back.
Recipe
Smoky Sweet Potato Tortilla Soup
Ingredients
For the Soup
- 2 tablespoons olive oil
- 1 yellow onion diced
- 1 jalapeno seeded and minced
- 4 cloves garlic minced
- 2 tablespoons tomato paste
- 1 tablespoon chili powder
- 2 teaspoons ground cumin
- 1 teaspoon smoked paprika
- 2 chipotle peppers in adobo minced, plus 1 teaspoon of the sauce
- 1 28-ounce can crushed fire roasted tomatoes
- 6 cups chicken or vegetable broth
- 1 ½ pounds sweet potatoes peeled and cut into ½ inch cubes
- 1 ½ teaspoons kosher salt plus more to taste
- 1 15-ounce can black beans drained and rinsed
- 1 ½ cups frozen corn
- 1 lime juiced, plus wedges to serve
For the Tortilla Strips
- 6 corn tortillas cut into ¼ inch strips
- ½ cup neutral oil for frying
- kosher salt for salting the strips hot
Toppings
- 1 avocado diced
- ½ cup cotija cheese crumbled
- ¼ red onion thinly sliced
- ¼ cup fresh cilantro chopped
Instructions
Build the Broth
- Heat the olive oil in a large pot over medium heat. Add the diced onion and minced jalapeno with a pinch of salt and cook 5 to 6 minutes, until the onion is translucent. Add the garlic for the last 30 seconds.
- Clear a space in the pot and add the tomato paste, chili powder, cumin, smoked paprika and the minced chipotle peppers with their adobo sauce. Stir in the oil for a full minute, until the paste darkens from bright red to brick, then stir it through the onions.
- Pour in the crushed fire roasted tomatoes and scrape the bottom of the pot. Add the broth and the kosher salt and bring it to a steady simmer.
Simmer and Finish
- Add the cubed sweet potato only once the liquid is simmering. Cook uncovered 12 to 15 minutes, testing at 12, until a knife slides in with slight resistance. Stir gently and rarely.
- Stir in the drained black beans and the frozen corn and cook 3 minutes, just to heat through.
- Take the pot off the heat, then stir in the lime juice and taste for salt. Adding lime off the burner keeps it bright.
Fry the Tortilla Strips
- Stack the corn tortillas, cut the stack in half, then cut across into ¼ inch ribbons.
- Heat the neutral oil in a small skillet until a test strip sizzles hard on contact. Fry the strips in two or three batches for 60 to 90 seconds, until the bubbling slows and they turn pale gold.
- Lift the strips onto paper towel and salt them immediately while the surface is still wet with oil. Serve the soup in bowls and add the strips at the table, with lime wedges and toppings.
Notes
- Brothy, not blended: nothing in this soup gets pureed. If the cubes break down and the broth clouds, you have overcooked it.
- Cut uniformly: ½ inch cubes, all the same size, or half will be mush before the rest is tender.
- Add potato to simmering liquid: starting from cold gives the cubes longer to break down at the edges.
- Lime off the heat: lime juice simmered in the pot turns dull and slightly bitter.
- Salt the strips hot: salt applied once they cool slides right off.
- Store strips separately: room temperature, loosely covered, 2 days. In the fridge they go limp.
- Chicken version: stir 2 cups shredded cooked chicken in with the beans and corn, use chicken broth, and start with 1 teaspoon of salt.
- Freezing: up to 3 months. Leave the avocado and strips off until serving.
