Beef Lombardi - cooking recipe

Ingredients

1 tablespoon olive oil
1 lb lean ground beef (90% lean)
1 onion, chopped
3 tablespoons tomato paste
4 garlic cloves, minced
3 (10 ounce) cans ro-tel original diced tomatoes and green chilies, drained
12 ounces wide egg noodles
1 1/4 cups sour cream
4 ounces cream cheese, softenened
1 tablespoon cornstarch
4 scallions, sliced thin
8 ounces colby-monterey jack cheese, shredded (2 cups)
salt
pepper

Preparation

Adjust oven rack to middle position and heat oven to 350 degrees. Grease 13 by 9 inch baking dish. Heat oil in 12-inch non stick skillet over medium-high heat until just smoking. Add beef, onion, 1 teaspoon salt, and 1 teaspoon pepper and cook, breaking up pieces with spoon, until beef is cooked through, about 8 minutes.
Stir in tomato paste and garlic and cook until fragrant, about 30 seconds. Stir in tomatoes and cook until most liquid has evaporated, 3 - 5 minutes. Remove from heat and set aside.
Meanwhile, bring 4 quarts water to boil in large pot. Add noodles and 1 tablespoon salt and cook, stirring often, for 3 minutes. Reserve 2 cups cooking water, then drain noodles.
Whisk sour cream, cream cheese, cornstarch, and 1/2 cup reserved cooking water together in now-empty pot until smooth. Stir in scallions, noodles, remaining 1.25 cups cooking water, and 3/4 teaspoon salt.
Spread noodle mixture in even layer in prepared baking dish. Spread beef mixture evenly over noodles. Sprinkle Colby Jack evenly over top. Bake until bubbling around edges and cheese is spotty brown, 25 - 30 minutes. Let cool for 15 minutes. Serve.