Bring a large pot of salted water to a boil. Add potatoes, and cook until tender but still firm, about 15 minutes. Drain, cool and mash.
Preheat oven to 350 degrees F (175 degrees C).
In a medium mixing bowl, combine mashed potatoes, 3/4 cup cheese, chili powder, cumin, garlic, salt and pepper. Spoon evenly into tortillas, and roll up. Place rolled tortillas side by side in a 8x8 inch baking pan. Spread enchilada sauce evenly over the top, and sprinkle with remaining cheese.
Bake in the preheated oven 15 minutes, or until cheese is bubbly.