Preheat your oven to 350°F (175°C) and line a baking dish with parchment paper for easy clean-up.
In a large skillet, heat a splash of oil over medium heat and sauté the diced onion and bell peppers for about 5-7 minutes until softened. Add the minced garlic and cook for another minute until fragrant. Remove from heat and allow to cool.
In a large mixing bowl, combine the ground beef and ground turkey. Add the sautéed vegetables, breadcrumbs, eggs, Worcestershire sauce, soy sauce, dried oregano, salt, and pepper. Mix until just combined—be careful not to overwork the meat.
Gently fold in the shredded provolone cheese, reserving a little for topping.
Form the meat mixture into a loaf shape and place onto the lined baking dish. Spread the ketchup evenly over the top and sprinkle the reserved cheese.
Bake in the preheated oven for 60-75 minutes, or until the meatloaf reaches an internal temperature of 165°F (74°C).
Once cooked, remove from the oven and let rest for about 10 minutes before slicing.
Notes
Serve slices on a platter garnished with fresh parsley and a side of roasted potatoes or a salad for a vibrant meal.