In a large skillet over medium heat, cook 1 lb ground beef until browned. Drain any excess grease.
Transfer the cooked ground beef to a crock pot.
Add 1 can (15 oz) pumpkin purée, 1 can (29 oz) tomato sauce, 2 cans (15 oz each) pinto beans with their liquid, 2 cups beef broth, 2 Tbsp chili powder, 1 tsp salt, 1 tsp black pepper, ½ diced onion, 1 diced red bell pepper, and 2 tsp minced garlic to the crock pot.
Stir all ingredients together until well combined.
Cover and cook on Low for 6–8 hours or on High for 3–4 hours.
Ladle the chili into serving bowls.
Top with 1 cup sour cream, 2 cups shredded cheese, and 2 sliced green onions, dividing the toppings evenly among the servings.
Serve warm and enjoy.
Notes
Refrigerate the leftovers in an airtight container for up to 5 days.