Rinse the pinto beans under cold water to remove debris.

If desired, soak the beans in water for at least 4 hours or overnight.

Chop the onion, bell pepper, and mince the garlic.

In a skillet, heat the olive oil over medium heat and sauté the onion, garlic, and bell pepper until soft.

Transfer the rinsed beans, sautéed vegetables, water, cumin, chili powder, salt, and pepper to the slow cooker.

Stir well to combine all ingredients evenly.

Cover the slow cooker and set it on low for 6 hours.

After 6 hours, check the beans for tenderness; they should be creamy and soft.

Once cooked, taste and adjust the seasoning as necessary.