Heat the oven to 450°F and arrange a rack in the middle. Meanwhile, shred 1 pound of sharp cheddar cheese. Line a baking sheet with aluminum foil. Spread about half of a 14-ounce bag of tortilla chips on the baking sheet in an even layer. Sprinkle half of the cheese evenly over the chips. Repeat with remaining chips and cheese. Bake until the cheese is melted and bubbly, about 5 minutes. Remove from the oven and garnish with your choice of toppings. Serve immediately.