Gather all the necessary ingredients. For a basic chili, you'll need ground beef (or another protein like turkey or chicken), canned diced tomatoes, tomato sauce, kidney beans, onion, garlic, chili powder, cumin, salt, pepper, and any other preferred seasonings or optional ingredients like bell peppers or jalapeños.
In a skillet over medium heat, brown the ground beef until it's fully cooked. Break up the meat with a spoon as it cooks to ensure it browns evenly. Drain off any excess fat.
Chop the onion and mince the garlic. If you're using any other vegetables like bell peppers or jalapeños, chop those as well.
Place the cooked ground beef, chopped onion, minced garlic, diced tomatoes, tomato sauce, drained kidney beans, and any additional vegetables or seasonings into the Crock-Pot. Stir everything together until well combined.
Set the Crock-Pot to the desired temperature setting (usually low or high) depending on how quickly you want the chili to cook. Cook on low for 6-8 hours or on high for 3-4 hours.
During the cooking process, it's a good idea to stir the chili occasionally to ensure that all the flavors meld together evenly.
About halfway through the cooking time, taste the chili and adjust the seasonings as needed. You may want to add more chili powder, cumin, salt, or pepper to suit your taste preferences.
Once the chili is fully cooked and heated through, it's ready to serve. Ladle it into bowls and garnish with toppings like shredded cheese, sour cream, chopped cilantro, or diced onions, if desired. Enjoy your homemade Crock-Pot chili!