Preheat the oven to 375°F (190°C). Line 1–2 large baking sheets with parchment paper or foil for easy cleanup.
In a large skillet over medium heat, add the ground pork sausage and ground beef. Cook, breaking the meat into small crumbles with a spatula, until fully browned and no pink remains, about 7–9 minutes.
1 pound ground pork sausage, 1 pound ground beef
Stir in the chopped onion and minced garlic. Cook for 3–4 minutes, until the onion softens and turns translucent.
1 small onion, 2 cloves garlic
Carefully drain off most of the fat from the skillet, leaving about 1–2 tablespoons so the mixture stays moist but not greasy.
Reduce the heat to low. Add the cubed processed cheese and shredded cheddar to the skillet. Stir often until the cheeses are fully melted and the mixture is smooth, thick, and glossy.
1 pound processed cheese, 1 cup sharp cheddar cheese
Stir in the Worcestershire sauce, Italian seasoning, crushed red pepper flakes (if using), paprika, salt, and black pepper. Taste carefully and adjust seasoning as needed.
1 teaspoon Worcestershire sauce, 1 teaspoon Italian seasoning, 1/2 teaspoon crushed red pepper flakes, 1/2 teaspoon paprika, salt, black pepper
Turn off the heat and let the sausage and cheese mixture sit for about 5 minutes. It should be warm and spreadable, not so hot that it soaks into the bread.
Arrange the cocktail rye bread slices in a single layer on the prepared baking sheets. Do not overlap so the bread can crisp properly.
1 loaf cocktail rye bread
Spoon about 1–2 tablespoons of the warm sausage and cheese mixture onto each slice of bread, spreading almost to the edges but leaving a small border.
1 pound ground pork sausage, 1 pound ground beef, 1 small onion, 2 cloves garlic, 1 pound processed cheese, 1 cup sharp cheddar cheese, 1 teaspoon Worcestershire sauce, 1 teaspoon Italian seasoning, 1/2 teaspoon crushed red pepper flakes, 1/2 teaspoon paprika, salt, black pepper, 1 loaf cocktail rye bread
Bake on the center rack for 8–10 minutes, or until the cheese is melted and bubbly and the bread edges are lightly toasted. For extra crisp edges, broil for 1–2 minutes at the end, watching closely.
Let the toasts cool for 1–2 minutes, then transfer to a serving platter. Serve warm while the cheese is still melty.