Grease the slow cooker. Spray the inside with non-stick cooking spray so nothing clings.
Combine ingredients. Add the cubed sweet potatoes, chopped onion, poblano, minced garlic, rinsed beans, kidney beans, fire-roasted tomatoes (with juices), vegetable broth, tomato paste, and all spices into the slow cooker. Stir well to combine so the paste and spices distribute.
Cook. Cover and cook on LOW for 8 hours, or HIGH for 4 hours, until the sweet potatoes are tender and the flavors meld. I usually go HIGH for 4 hours on weeknights — less waiting, same comfort.
Serve. Spoon into bowls and let everyone choose toppings. Tortilla chips and avocado make it feel like a party.
Note: If the chili gets too thick, stir in a splash of broth. If it seems thin, remove the lid and cook on HIGH for 15–20 minutes to reduce.
Tips for better results (chef mom hacks)
Cut sweet potatoes uniformly. Even cubes cook evenly and prevent some pieces from falling apart.
Toast spices for 30 seconds in a dry pan before adding if you want a deeper aroma — I do this when I remember and it’s worth it.
Taste and adjust at the end. Salt and acid (a squeeze of lime or a splash of apple cider vinegar) brighten chili dramatically.
Add texture: stir in a can of drained corn or top with toasted pepitas for crunch.
If you like heat: add an extra poblano or a chopped chipotle in adobo. If you fear the spice, leave it out — the chili still sings.