01 - Preheat oven to 375°F (190°C). Lightly grease a 12-cup muffin tin.
02 - Boil macaroni in salted water until just al dente, about 6 minutes. Drain and set aside.
03 - Melt butter in a saucepan over medium heat. Stir in flour and cook for 1 minute, then slowly whisk in milk. Cook, stirring, until the sauce thickens, about 2–3 minutes.
04 - Remove sauce from heat. Mix in grated cheddar and mustard powder until smooth. Season with salt and pepper. Add macaroni and stir to coat. Allow mixture to cool slightly.
05 - In a large mixing bowl, combine ground beef, ground pork, breadcrumbs, milk, egg, onion, garlic, ketchup, Worcestershire sauce, salt, pepper, and thyme. Mix until just combined.
06 - Press about 2 tablespoons of meat mixture into the bottom and up the sides of each muffin cup, forming a well in the center.
07 - Spoon a heaping tablespoon of mac and cheese into each meatloaf well.
08 - Cover the macaroni centers with a thin layer of remaining meat mixture, sealing the tops. Sprinkle each muffin with extra cheddar cheese.
09 - Bake for 25–30 minutes, until meat is fully cooked and tops are golden.
10 - Allow muffins to cool for 5 minutes before carefully removing from tin. Serve warm.