01 - Preheat oven to 375°F. Line a baking sheet with parchment paper or lightly grease a 9x5 inch loaf pan.
02 - In a large mixing bowl, combine ground beef, eggs, 1 cup Parmesan cheese, milk, garlic, onion, parsley, breadcrumbs, salt, pepper, Italian herbs, and red pepper flakes. Mix gently until just combined—do not overmix to maintain tender texture.
03 - Shape the mixture into a loaf on the prepared baking sheet or press firmly into the loaf pan, smoothing the top evenly.
04 - Spread the tomato sauce or ketchup evenly over the top surface, then sprinkle with the remaining 1/3 cup Parmesan cheese.
05 - Bake for 50 to 55 minutes until the center reaches 160°F when checked with a meat thermometer. The topping should be lightly caramelized.
06 - Let the meatloaf rest for 10 minutes before slicing to allow juices to redistribute. Garnish with extra fresh parsley and serve warm.