This comforting dish always makes my taste buds sing!

12 oz kielbasa sausage, sliced
8 oz elbow macaroni or other pasta of choice
2 cups shredded cheddar cheese
1 cup shredded mozzarella cheese
1 cup milk
2 tablespoons all-purpose flour
2 tablespoons unsalted butter
1/2 teaspoon garlic powder
1/2 teaspoon onion powder
Salt and pepper to taste
1/4 cup grated Parmesan cheese
2 tablespoons chopped fresh parsley (optional, for garnish)