Ingredients
Olive oil, for pan
4 slices white bread, torn into pieces
2 1/2 pounds ground beef
1 medium yellow onion, peeled and cut into eighths
2 cloves garlic
2 stalks celery, cut into 2-inch pieces
2 carrots, peeled and cut into 2-inch pieces
1/2 cup flat-leaf parsley leaves
1 large egg
1 cup ketchup, divided
3 teaspoons dry mustard, divided
1 tablespoon coarse salt
2 teaspoons freshly ground black pepper
2 tablespoons brown sugar
Preparation
Heat oven to 375 degrees. Line a rimmed baking sheet with parchment paper, then fit the sheet with a wire rack. Brush an 10-by-4 3/4-by-3-inch loaf pan with oil, and place on rack; set aside. Place bread in the bowl of a food processor fitted with the steel blade; pulse until fine crumbs form. Transfer to a medium bowl, and add ground beef.
Place onion, garlic, celery, carrots, and parsley in the bowl of a food processor fitted with the steel blade; pulse until fine. Add to meat mixture, using hands to mix well. Add egg, 1/2 cup ketchup, 2 teaspoons dry mustard, salt, and pepper; use hands to combine thoroughly. Transfer to prepared loaf pan.
Combine remaining 1/2 cup ketchup, remaining teaspoon dry mustard, and brown sugar in a bowl; stir until smooth.
Brush mixture over meatloaf; place pan in oven, atop prepared wire rack set on parchment-lined baking sheet. Cook until a meat thermometer inserted in the center reads 160 degrees, about 90 minutes. If top gets too dark, cover with foil and continue baking.
