Ingredients

• 1 tablespoon vegetable oil
• 1 onion, chopped
• 1 clove garlic, minced
• 4 tomatoes, chopped
• 2 cups chopped cooked roast beef
• 1 (8 ounce) jar prepared taco sauce
• 1 (4 ounce) can diced green chile peppers
• 1/2 teaspoon cumin
• 1/8 teaspoon red pepper flakes, or to taste (optional)
• 6 (7 inch) flour tortillas, warmed
• 1 1/2 cups shredded Cheddar cheese
• 2 cups shredded lettuce