Double-Layer Beef Tacos

Inspired by the popular taco option for quick cooking, our taco turns out to be larger and has a bright, fresh taste, but at the same time surpasses the finished original in its qualities.
Preheat the grill to high heat.Preheat a large skillet over medium-high heat. Add the butter; stir to coat. Add the onion; simmer for 4 minutes, stirring occasionally. Add the garlic and the following 6 ingredients (with the addition of black pepper); simmer for 1 minute, stirring constantly. Add the beef; cook for 3 minutes or until it is browned, stirring until it crumbles. Remove the beef mass from the mold with a slotted spoon; dry on paper towels. Return the beef mixture to the pan; add the tomato sauce. Cover, reduce heat and simmer for 10 minutes, stirring occasionally.Spread 2 tablespoons of beans evenly on 1 side of each flour tortilla; sprinkle each with about 2 tablespoons of cheese. Place the tortillas on a baking sheet; bake for 2 minutes or until the cheese is melted. Carefully wrap 1 tortilla around 1 hard taco shell, pressing lightly until the cheese sticks to the shell. Repeat with the remaining tortillas and shells. Add about 1/4 cup of the beef mixture to each pan; top with 2 tablespoons of lettuce leaves, 2 tablespoons of tomatoes, and 1 tablespoon of sour cream.