Preheat oven to 375°F and grease a 9x13-inch baking dish. Cook egg noodles until al dente, drain, and set aside with ½ cup reserved pasta water.

Heat olive oil in skillet. Brown kielbasa for 3-4 minutes. Remove and set aside, leaving drippings in pan.

Sauté onions in the same pan for 3 minutes. Add bell peppers, cook 2 more minutes. Stir in garlic and cook for 30 seconds.

In a bowl, whisk sour cream, cream cheese, chicken broth, paprika, thyme, salt, and pepper until smooth.

Combine noodles, kielbasa, vegetables, and tomatoes in baking dish. Pour sauce over and mix gently. Top with cheddar cheese.

Cover with foil and bake for 20 minutes. Remove foil and bake 10-15 minutes more. Let rest for 5 minutes before serving.