Mash and sauté sausage, chopped onion, and garlic until sausage is browned.

Drain excess grease.

Add crushed tomatoes, tomato sauce, tomato paste, parsley, dried basil, pepper, and sugar to the sausage mixture.

Simmer uncovered for 1 hour, or until the sauce has thickened.

In a separate small bowl, mix ricotta cheese, eggs, pepper, and parsley.

Grease a 9 x 13-inch baking dish.

Layer half of the cooked lasagna noodles in the dish.

Spread half of the ricotta cheese mixture over the noodles.

Spoon half of the sausage sauce mixture over the ricotta cheese.

Repeat the layers: noodles, ricotta cheese mixture, sausage sauce mixture.

Sprinkle mozzarella cheese evenly over the top.

Sprinkle parmesan cheese over the mozzarella.

Bake uncovered in a preheated oven at 350°F (175°C) for 45 minutes.

Let the lasagna rest for 15 minutes before cutting and serving.