Heat a large skillet over medium-high heat and add the chopped onion. Cook the onions for approximately 5–7 minutes, stirring occasionally, until they become soft, translucent, and slightly golden around the edges. If you prefer deeper sweeter flavor, you can continue cooking a little longer until the onions begin lightly caramelizing. This step builds the savory flavor foundation for the entire chili.
Add the minced garlic into the skillet and stir continuously for about 30–60 seconds until fragrant. Be careful not to burn the garlic because it can become bitter very quickly. The garlic should smell rich and aromatic while blending beautifully into the onions.
Add the ground beef to the skillet and begin breaking it apart using a wooden spoon or spatula. Continue cooking for approximately 8–10 minutes until the beef is fully browned and no pink remains. Stir occasionally so the meat cooks evenly and develops flavorful browned edges that add extra richness to the chili.
Once the beef is fully cooked, carefully transfer the entire beef and onion mixture into a large slow cooker or crock pot. If there is excessive grease in the skillet, you can drain some off first to prevent the chili from becoming too oily.
Add the diced tomatoes with their liquid, tomato paste, green chiles with liquid, Worcestershire sauce, chili powder, cumin, oregano, sea salt, and black pepper directly into the slow cooker. The combination of tomatoes and spices creates the thick rich chili base while the green chiles add subtle smoky flavor and gentle heat.
Stir everything thoroughly until all the ingredients and seasonings are fully combined. Make sure the tomato paste gets evenly mixed throughout the chili so there are no thick concentrated spots remaining at the bottom.
Place the bay leaf gently into the center of the chili mixture if using. The bay leaf slowly releases additional savory depth while the chili simmers low and slow.
Cover the slow cooker with the lid and cook the chili on LOW for 6–8 hours or HIGH for 3–4 hours. During this time, the flavors blend together beautifully and the chili thickens into a rich hearty consistency. The longer it cooks, the deeper and more comforting the flavor becomes.
Once the chili has finished cooking, remove the bay leaf and discard it before serving. Taste the chili and adjust the seasoning if needed by adding extra salt, pepper, or chili powder depending on your personal preference.
Ladle the hot keto chili into serving bowls and top with your favorite low-carb toppings such as shredded cheddar cheese, diced avocado, sour cream, sliced jalapeños, chopped cilantro, or green onions. Serve warm while the chili is thick, rich, and comforting for the ultimate keto comfort food dinner.