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.