In a large pan set over medium heat, sauté the Onion (1 1/2 cup) and Garlic (2 clove) in Olive Oil (3 tablespoon) until the onions are translucent.
Add the Sweet Potato (4 cup), Chili Powder (1 teaspoon), Ground Cumin (1 teaspoon), and Cayenne Pepper (1 pinch) and cook, covered, for about 10 minutes, stirring every few minutes.
When the sweet potato is tender, add Salt and Pepper (to taste) and remove the pan from the heat. Sprinkle Lime Juice (to taste) over the sweet potatoes, mix, taste, and adjust with more lime and salt to taste.
Spread 1/8th of the filling over each White Corn Tortilla (8). Top with Sharp Cheddar Cheese (1 cup) to taste.
Bake in a 350 degrees F (180 degrees C) oven until the cheese is fully melted and the sweet potatoes and tortillas are hot, approximately 15 minutes.
Remove pan from the oven, and fold each tortilla in half. Serve with more Lime Juice (to taste), Sour Cream (to taste), and Salsa (to taste) on the side.