Finely dice the onion. Slice the chili. Mince the garlic. Drain and rinse the beans (if using canned). Mix the spices.
Heat the oil in a large skillet over medium-high heat. Once hot, add the onions and sauté for 2 minutes. Add the minced garlic and sauté for another 10 seconds.
Add the beef and cook it for 4-5 minutes stirring to make sure it's browned from all sides.If you're using fattier meat, drain any excess fat before moving on to the next step.
Add the mixed spices to the skillet, mix well, then remove from the heat.
Add the browned mince with the rest of the ingredients in the crockpot (onion, garlic, red kidney beans, tomato paste, green chilis, crushed tomatoes) and cook on LOW for around 4 hours in the crockpot.
Serving
You can serve it with avocado, sour cream, tortilla chips, shredded cheese, and lime, or make a burrito bowl. Check the main post for more ideas.
Video
Notes
To Make It Milder: Leave out the additional chili pepper or replace it with a green bell pepper. You can also add a spoonful of sour cream or Greek yogurt to the tomato paste to help balance out the heat.To Make It Spicier: You can add some chipotle in adobo sauce, use ground and fresh chilies (think serrano peppers that have a higher heat level) or add a few dashes of hot sauce (sriracha works great with chili).