Slow Cooker Vegetarian Chili

• 1 medium red onion chopped
• 1 red bell pepper chopped
• 1 yellow bell pepper chopped
• ½ green bell pepper chopped
• 8 cloves garlic minced
• 1 1/2 tablespoon prepared chili powder
• 2 tablespoons ground cumin
• 1 tablespoon unsweetened cocoa powder
• salt & pepper
• 3 cans fire roasted tomatoes
• 2 cans black beans drained and rinsed
• 1 can Kidney Beans drained and rinsed
• 1 can White beans drained and rinsed
• 1 pound sweet potato peeled and cut into 1/2-inch pieces
• ¼ cup cilantro chopped

Optional, for serving

• Sour cream and extra cilantro