Place stewed beef or boneless chuck roast chunks in the slow cooker. Add all dry spices and seasonings to beef and stir until well combined.
Chop the yellow onion and seed and dice the jalapeño pepper. Add to beef in slow cooker.
Next, add the rest of the ingredients to the beef mixture and stir until well combined. Cook on LOW for 6 to 8 hours.
How to Thicken Chili: Tomato paste is used to thicken the chili. If your dish is still too thin, you may add a roux of cornstarch and water to your desired thickness. Add half a cup of water to a bowl and stir in 2 Tablespoons cornstarch until blended smooth. Slowly add the cornstarch, stirring the chili, until thickened. Add this at hour 5 and continue cooking as directed.