Place all the ingredients for the meatballs in a mixing bowl. Mix with your hands (or a fork) until everything well combined. Cover with plastic and refrigerate for 20 minutes to allow the chia seeds to work their gelling magic. (Use this time to prep your vegetables.)
Pre-heat the oven to 375 degrees. Line a baking sheet with foil. Spray a wire rack with cooking spray and place it on the prepared baking sheet. (If you don’t have a wire rack, don’t panic. You can bake your meatballs directly on the foil-lined baking sheet. They may ooze a little bit of liquid as they cook, but it’s not a big deal.)
With damp hands, form the meatball mixture into balls roughly 2-inches in diameter. You should have about 18 meatballs, dudes.
Bake for 22 minutes until cooked through.
While the meatballs are in the oven, get going on the vegetables. Heat the olive oil in a large (12- to 14-inch) ovenproof skillet over medium-high heat. When the oil is hot and shimmering, add the bell peppers and onion and cook for 10-12 minutes until the vegetables are softened (but not mushy!) and lightly browned in spots.
Add the garlic, chili powder, smoked paprika, cumin, cayenne (if using), and a generous pinch of kosher salt. Cook for 1 minute until the spices are toasted and fragrant. Stir in the beans and fire roasted tomatoes. Taste and season with a little extra salt and cayenne if necessary.
Turn off the heat and nestle the meatballs in the vegetable mixture.
Top with the cheddar cheese in an even layer. Pre-heat the broiler on high.
Place the skillet under the broiler and broil until the cheese is melted and bubbling, about 2 minutes.
Shower the skillet with freshly chopped cilantro if you’re feeling fancy and serve piping hot with your finest hot sauce.