Heat olive oil in a large sauce pan over medium-high heat.
Add the taco seasoning and garlic powder, and cook about 1 minute, stirring often.
Mix in the black beans, green chiles, and water. Then bring to a simmer.
Cover, reduce heat, and simmer for 10 minutes.
Remove cover, add salt & pepper and mash half the beans with a potato masher. Cook an additional 3 minutes, then cover and set aside.
Cover a Large Sheet Pan with foil, and spray with cooking oil (or brush on some oil).
Place 12 corn tortillas in one layer onto the sheet pan (they may overlap slightly), then spray the tops with cooking oil (or brush with oil).
Bake at 400ºF for 4 minutes, on the middle rack.
Remove from oven, and flip all of the tortillas.
Fill each tortilla with about 2 tablespoons of bean mixture on the center of one side.
Fold over the tortilla, and lighlty press down on the edges to keep shut.
Return to the oven, and bake an additional 5-7 minutes per side, until each side is lightly browned.
Serve alone, or fill with your favorite taco toppings!