01 -
Heat a large skillet over medium heat. Add ground beef and cook, breaking it apart with a spatula, until fully browned, about 5-7 minutes. Drain excess grease.
02 -
Reduce heat to low, stir in 1 cup marinara sauce, and simmer for 2-3 minutes until heated through. Remove from heat and set aside.
03 -
In a medium bowl, combine ricotta cheese, grated Parmesan, and Italian seasoning. Mix thoroughly to create a smooth filling.
04 -
Spread ½ tablespoon of softened butter evenly on one side of each sourdough bread slice.
05 -
On the unbuttered side of four bread slices, layer 2 tablespoons ricotta mixture, ⅓ cup ground beef mixture, and ¼ cup shredded mozzarella each. Repeat for each sandwich.
06 -
Top each assembled slice with a remaining slice of bread, buttered side facing out.
07 -
Heat large skillet over medium heat. Cook sandwiches one or two at a time for 3-4 minutes per side until golden brown and cheese is melted.
08 -
Serve immediately with remaining marinara sauce on the side for dipping.