In a skillet, cook the ground beef until browned over medium high heat.
Drain any extra oil from the meat.
Mix taco seasoning with add water and cornstarch, pour over beef and stir on low heat until the sauce thickened.
Heat small corn tortillas in the microwave for 30 seconds so they are soft enough to fold without breaking.
Fill the tacos with beef, add in beans if desired, and add grated cheese, then stack them overlapping on a baking sheet, lay a strip of foil over top to hold them down if they start popping up. I rolled a piece of foil the length of the baking sheet and just laid it on top of the tacos.
You can add in some sliced black olives, jalapenos, green onions, or your favorite taco toppings, or you can add them on top tacos after they are baked.
Place the tacos in the oven for 5-10 minutes until the cheese has melted and they are lightly toasted.
You can prep them out and place them in the fridge covered, then heated in the oven. This makes them perfect to have them all ready one once.