1. Cut tofu crosswise into 4 slices. Place tofu slices on several layers of heavy-duty paper towels; cover with additional paper towels. Let stand 30 minutes, pressing down occasionally.
2. Combine basil and next 8 ingredients (through garlic) in a large zip-top plastic bag. Add tofu to bag; seal. Marinate in refrigerator 1 hour, turning bag occasionally.
3. Place flour in a shallow dish. Place egg substitute in another shallow dish. Place panko in another shallow dish.
4. Remove tofu from marinade, reserving remaining marinade. Working with one tofu piece at a time, dredge tofu in flour, shaking off excess. Dip tofu in egg substitute, allowing excess to drip off. Coat tofu completely with panko, pressing lightly to adhere. Set aside. Repeat procedure with remaining tofu, flour, egg substitute, and panko.
5. Heat a large nonstick skillet over medium-high heat. Add olive oil to pan, swirling to coat. Add tofu to pan; reduce heat to medium, and cook for 4 minutes on each side or until browned. Remove tofu from pan, and keep warm.
6. Combine reserved marinade, walnuts, and bell peppers in a blender; process until smooth (about 2 minutes). Pour bell pepper mixture into pan; cook over medium-high heat 2 minutes or until thoroughly heated. Serve with tofu.