For me, the required element for a good chili is that when you finish a bowl, you want another bowl. I'm going to share a few ways to increase the umami or savoury aspects of your chili.
When I am talking chili, I'm not going to get into the merits of beans/no beans, Texas chili or bust or any of those great and valid debates. I'm going to assume the thing that you get when you go to a soup counter or at the local lunch time place is what we are talking about. Some of these tips apply regardless.
I'm not going to regale you with tales of the new Naga Scorpion hybrid that someone smuggled for me or the latest capsaicin extract or even the relative fruitiness of some of the mid Scoville range peppers. If you didn't understand the last paragraph, then I'm talking to you. Those other food nerds can go to Chile Pepper.
I'm going to share a few ways to increase the umami or savoury aspects of your chili.
Reduce the Water
The enemy of intense, rich flavours is water. For many of your ingredients, you want to get water out and maybe replace it with a different liquid.
Start by looking at the vegetables that you add but let's leave the onions until later. If you add carrots and celery, chop them (it reduces time) and try roasting them in a 250C oven until they have lost some water.
Roast or cook down tomato paste before adding. If you over reduce or find that you need to loosen up the tomato paste, add a liquid that will add depth such as stock, malty beer or that tomato water from the can of tomatoes you usually add.
If you are using chili powder, take a few seconds and toast it in a dry pan over a low heat. Keep mixing or swirling it around so it doesn't burn but there you go.
Be brave and make your own spice mixture. Toast the spices and grind them together. Last time I made chili, I took cumin seed and star anise (more on the star anise later) toasted them and then ground just the cumin. I toasted some ground spices; cinnamon, allspice, sweet paprika, sweet-sour paprika, and cayenne. This was my spice base.
Buy your own dried peppers and toast them. Ancho, pasilla and New Mexico are often available in stores. Any of the dry smoky ones are best. Leave the seeds in, if you like the heat. You can even improve these peppers by doing the next hint.
Use Dried Ingredients
This works especially well, if you are using ingredients to build umami. Dried mushrooms, sundried tomatoes and parmesan rinds work well for building flavour. Those are the quick fixes.
Beans. Take the time to soak and cook your own beans. That way, you can get the texture to your preference. Do up extra and freeze or make baked beans. Mix up the type of beans. Colour, texture and flavour differ between beans and these differences can add complexity.
Another great trick is to reconstitute these dried ingredients using warm stock, beer, or even excess bean water from cooking the beans. For instance, using a malty beer to make a mushroom tea and then adding that to the chili pot will definitely add a layer of flavour. You can use the reconstitution method along with the toasting method to compound flavours. Toast dry chiles, reconstitute them and use a blender to make a sauce and add it to the chili pot.
A little smoke can add depth. Anything from using smoked chili peppers, smoked paprika, liquid smoke or a bit of bacon can put another layer of moreness into the bowl.
Add Flavour Early
The earlier the flavour is added in the process, the more time it has to develop. For instance, if you sweat the onions, add the spices and the dried carrots. Drying the carrots before adding them is earlier than add the carrots later. I added star anise when browning the beef. Star anise has a slight liquorice flavour when noticeable. When added at a low level, it makes meat tastes meatier. I also toasted star anise with spices and when I took them out, added the stars to the tomato paste that I was reducing.
Cheats Are Additive
This time I added smoked sundried tomatoes that had been soaked in warm beer. I toasted smoked paprika and added them to the onions. You could use a rauchbier which is a smoked beer as the liquid for your peppers, tomatoes or extra liquid.
You don't need to do all of these to make a chili with depth and umami. If you just do a few of these, they will improve it. There are other cheats but these are the ones that make me happy. Try a few out. Let me know how it goes.