01 - Preheat oven to 375°F. Lightly grease a 9x13 inch baking dish with cooking spray or butter.
02 - Bring a large pot of salted water to boil. Cook egg noodles according to package directions until al dente, typically 6-8 minutes. Drain thoroughly in a colander and set aside.
03 - Heat olive oil in a large skillet over medium heat. Add diced onion and red bell pepper; sauté for 3-4 minutes until softened and translucent.
04 - Add ground beef to the skillet. Cook for 6-7 minutes, breaking up with a spatula, until fully browned. Drain excess fat from the skillet.
05 - Stir in minced garlic and cook for 1 minute until fragrant. Add tomato paste, drained diced tomatoes, frozen peas, Italian herbs, paprika, salt, and black pepper. Cook for 3-4 minutes to meld flavors.
06 - Remove skillet from heat. Fold in sour cream and cream of mushroom soup until fully incorporated and smooth.
07 - Add half the shredded cheddar cheese and the cooked noodles to the meat mixture. Gently fold until evenly distributed.
08 - Transfer the mixture to the prepared baking dish, spreading evenly. Sprinkle the remaining cheddar cheese over the top in a uniform layer.
09 - Bake for 25-30 minutes until the cheese is melted and golden brown, and the edges are bubbling. Let rest for 5 minutes before serving to allow the casserole to set.