1. Combine 1 cup onion, 1 cup bell pepper, cilantro, oregano, garlic, and ancho chile peppers in a food processor; process until almost smooth. Heat oil in a large skillet over medium heat. Add onion mixture to pan; cook 8 minutes or until liquid nearly evaporates, stirring frequently. Add cumin and next 6 ingredients (through bay leaf); cook 2 minutes, stirring frequently.
2. Transfer mixture to a 6-quart electric slow cooker. Stir in remaining 2 cups onion, 1 cup bell pepper, broth, beans, tomato puree, and beer; cover and cook on LOW 8 hours.
3. Stir in remaining 1 cup bell pepper, zucchini, and diced tomatoes; cook on LOW 30 minutes or until vegetables are tender. Discard bay leaf. Top chili with sour cream and crushed corn chips.