Preheat your oven to 400°F (200°C).

Arrange the hard taco shells upright in the baking dish.

Cook the ground beef with the onion in a skillet over medium heat for 5-7 minutes until browned.

Stir in the minced garlic and taco seasoning; cook for another minute.

Add tomato sauce or salsa to the mixture and let simmer for 5 minutes.

Fill taco shells with the beef mixture and top with shredded cheese.

Bake the tacos in the oven for 10-15 minutes until cheese is melted and bubbly.

Remove from the oven and top with fresh garnishes before serving.