01 -
Preheat the oven to 350°F.
02 -
In a skillet, heat olive oil over medium heat. Add onion and ground beef; cook until browned and onions are translucent. Season with salt and pepper.
03 -
Stir in tomato paste, garlic, Italian seasoning, celery salt, and drained tomatoes. Cook for 5 more minutes.
04 -
Boil egg noodles for 3 minutes. Reserve 2 cups of noodle water before draining.
05 -
In a bowl, whisk together sour cream, softened cream cheese, cornstarch, and ½ cup of reserved noodle water until smooth.
06 -
Mix the cooked noodles with the remaining reserved noodle water, then transfer to a greased 9x13-inch baking dish. Spread the beef mixture evenly on top.
07 -
Sprinkle shredded Colby Jack cheese over the casserole.
08 -
Bake for 25-30 minutes, or until the cheese is bubbly and golden.