In a large seasoned skillet or 5-6 quart Dutch oven, brown the beef and garlic over medium-high heat until it's cooked through. Remove the beef onto a plate and drain off the excess fat. Tip: while the beef cooks, measure out your seasonings onto a small dish.
Add the oil, onions, celery, carrots, and seasonings to the skillet and cook for about 7 minutes, until the onions are translucent and the veggies have softened a little. Add the zucchini, stir, and cook them for 2 more minutes while stirring.
Add the cooked beef back in, pour the tomato sauce and diced tomatoes into the pot, and stir to mix everything. Bring the mixture to a boil, while stirring from time to time.
Simmer
Reduce the heat to the lowest setting and simmer the paleo chili for 20 to 25 minutes, stirring it from time to time.
Serve and store
Serve warm, with your favorite paleo-approved toppings.
Once cooled, transfer chili leftovers into an airtight container and keep in the fridge for up to 4 days. Or, freeze it for up to 3 months.
Notes
To thin out this chili, add 1 cup of water, broth, or stock. For a soup-like consistency, add 2-4 cups of broth or stock. Ingredient swaps:
Carrots for Sweet potatoes, same amount diced.
Zucchini for Butternut squash: fresh or frozen, both work.
Ground beef for ground turkey or chicken: A leaner option, though less fatty and slightly drier.
Other add-ins:
Add 8 ounces of sliced mushrooms with the veggies for extra depth of flavor.