Preheat the oven to 425°F.
In a large ovenproof skillet, heat olive oil over medium heat.
Add ground beef and cook until browned.
Add onion, bell pepper, and garlic, and cook until softened.
Stir in tomatoes, beans, beef stock, chili powder, cumin, salt, and pepper.
Simmer for about 15 minutes, allowing flavors to develop.