Brown the ground beef in a large skillet over medium heat. Add the diced onion and cook until softened.

Stir in 3 minced garlic cloves, the marinara sauce, oregano, salt, and pepper. Simmer the sauce for 10 minutes.

Cook the lasagna noodles according to package directions until al dente, then drain them.

Spread a thin layer of meat sauce in the bottom of a baking dish. Add a layer of noodles, followed by half the ricotta and one third of the mozzarella. Repeat the layers once more, then finish with remaining sauce and mozzarella.

Bake the lasagna at 375°F for 25 minutes until the cheese is bubbly and lightly browned.

While the lasagna bakes, mix the remaining minced garlic clove with the softened butter and chopped parsley. Slice the French bread loaf, spread the garlic butter on each piece, and place on a baking sheet.

Bake the garlic bread during the last 10 minutes of the lasagna cook time until the edges turn golden.