1. Adjust an oven rack to the middle position and heat the oven to 350 degrees. Spray a 9 by 5-inch loaf pan with non-stick cooking spray, then sprinkle 1/2 cup of the Parmesan evenly over the bottom of the pan.
2. In a large bowl, whisk the flour, baking powder, cayenne, salt, and pepper to combine. Using a rubber spatula, mix in the cheddar, breaking up clumps. In a medium bowl, whisk together the milk, melted butter, egg, and sour cream. Using a rubber spatula, gently fold the wet ingredients into the dry ingredients until just combined (the batter will be heavy and thick). Do not over-mix. Scrape the batter into the prepared loaf pan; level the surface with a rubber spatula. Sprinkle the remaining 1/2 cup Parmesan evenly over the surface.
3. Bake until deep golden brown and a toothpick inserted into the center of the loaf conies out clean, 45 to 50 minutes. Cool in the pan on a wire rack 5 minutes; invert the loaf onto the rack, turn right-side up, and continue to cool until warm, about 45 minutes. Cut into slices and serve.
VARIATION: QUICK CHEESE BREAD WITH BACON, ONION, AND GRUYERE; Cut 5 ounces (5 slices) bacon into 1/2-inch pieces and fry in a medium nonstick skillet over medium heat, stirring occasionally, until crisp, about 8 minutes. Using a slotted spoon, transfer the bacon to a paper towel-lined plate and pour off all but 3 tablespoons fat from the skillet. Add 1/2 cup minced onion to the skillet and cook, stirring frequently, until softened, about 3 minutes; set skillet with onion aside.
Follow recipe for Quick Cheese Bread, substituting Gruyere for cheddar, adding the bacon and onion to the flour mixture along with the cheese, and omitting the butter.