01For the meatloaf: Preheat oven to 375 degrees. Place a large skillet over medium heat, and add the olive oil, onions and garlic. Sauté until translucent and tender, 3 to 4 minutes. Remove from heat and set aside to cool.
02In a large mixing bowl, combine ground beef, eggs and milk. Mix well by hand, and add bread crumbs, mustard, barbecue sauce, horseradish, and cooked onions and garlic. Mix again, and add the parsley, salt, pepper and thyme. Mix well until thoroughly combined.
03Spread the croutons across a shallow 8-inch-square baking dish. Top with the meatloaf mix, patting the surface so it is level. Bake until the internal temperature reads 165 degrees on an instant-read thermometer and the top is nicely browned, about 1 hour. Toward the end of baking, prepare the chili shrimp.
04For the chili shrimp: In a small mixing bowl, combine the chili powder, cayenne pepper, paprika and flour. Dredge the shrimp in the mixture until well coated. Place a small skillet over medium heat, and add the chili oil. When it is hot, add the shrimp and cook for 2 minutes a side.
05To finish, cut the meatloaf into 4 slices. Place a slice on each of 4 plates, and top with a chili shrimp. If desired, serve with mashed potatoes.