Full-On Taco Bar

Name: Full-On Taco Bar
Cuisine: American, Mexican, Latin American
Ingredients: 2 large sweet onions, chopped (2 cups); 1 red bell pepper, chopped (1 cup); ½ fresh jalapeño pepper, seeded and finely chopped; 2 cloves garlic, minced; 3 cups cooked brown lentils or two (15-ounce) cans lentils, drained and rinsed; 1 (15-ounce) can fat-free vegetarian refried beans; 1 cup vegetable stock or water, plus more as needed; ¼ cup reduced-sodium taco seasoning mix; 12 6-inch corn tortillas, warmed; Toppings such as shredded lettuce, chopped tomatoes, red onion, avocado, fresh cilantro, and salsa or taco sauce