You can get many different flavours out of an onion based on how you cook it. One that is charred on the grill or under the broiler has its own unique flavour. As does a caramelized onion. One that has been deep fried does not taste the same as one that has been briefly sauteed. Yes, all of these will taste like onions. But, they all have their own unique subtleties.

Building flavour is all about subtleties. Using time, and different techniques to build layers into your dish. Layering really is the key.

How to Layer Flavour

If you were making a bolognese sauce, you typically wouldn’t just throw everything in a pot and hope for the best. You would brown the beef and set it aside. Lightly caramelizing the onions would add a touch of sweetness. Cooking some chili flakes with the onions would draw their flavour out into the cooking oils. Next you would add some garlic and cook that out. Then some tomato paste and cook that out as well. You would then add the browned beef back into the pot. Red wine could be added and allowed to reduce. Next you could add some beef stock and let that reduce. Then the tomatoes. Salt and pepper. Then you would let it all simmer. This is the technique for building flavour.

Of course, you could brown the beef, throw the rest of the ingredients in at the same time and hope for the best. This sauce would be edible, but would it be enjoyable? Probably not.

In order to really understand layering flavours you must first have a basic understanding of the chemical changes happening in your food. Now, to be clear, I mean the most basic understanding. More than anything, you just need to think about what’s happening to your food.

Think of tomato paste for example. On it’s own it generally has a slightly metallic taste. Adding it to your dish as is will simply transfer that flavour to your food. However, if you take the time to cook it out, its flavour will transform. You can take this metallic paste, and make it sweet and balanced, simply by cooking it in some oil. Generally, the tomato paste would be added to the onions after they have been sauteed and just prior to adding any liquid ingredients.

If we take a second and look back at our bolognese sauce example, we can see something interesting. Tomatoes are acidic which is balanced by sweetness. It maybe common to just add a spoonful of sugar to a bolognese sauce, and depending on the tomatoes it may be needed. But, if you take the time to lightly caramelize the onion, and cook out the tomato paste, that sweetness will be built in. This means there will be less of a need to add sugar, because you are drawing that sweetness out of the ingredients naturally.

Another takeaway form the bolognese example would be the addition of the liquids. The wine and the stock. These liquids weren’t just added together and then topped with the tomatoes. Add the liquids individually and allow them time to reduce. Reducing the liquid simply means to evaporate the liquid thus concentrating the flavour. For the wine this also removes some of the harsh alcoholic flavours.

It takes thought to cook like this. It can not be a mindless effort or you end up with mindless food. However, once you wrap your head around this idea of layering, and building flavour, it becomes second nature. Especially, when you taste the difference.