Non-stick cooking spray
Kosher salt, to taste, as needed
freshly ground black pepper, to taste, as needed
1 lb spaghetti, variety of your choice
1 lb 80-90% lean ground beef
1 Tbsp olive oil
1 medium yellow onion, chopped
2 C marinara sauce, homemade or store-bought
1/2 C whole-milk ricotta cheese
2 Tbsp minced fresh flat-leaf parsley
3 large eggs
1/2 C plus 2 Tbsp grated Parmesan
1 C shredded mozzarella
Preheat oven to 350 F degrees. Grease a 9 inch cake pan with non-stick cooking spray.
Cook spaghetti until al dente. Drain and set aside.
In a large skillet, over medium-high heat, brown ground beef. Season with salt and pepper.
Transfer to a paper towel-lined plate to drain. Wipe skillet clean.
Heat olive oil, over medium heat, and sauté onions until translucent. Set aside.
In a large bowl, whisk marinara, ricotta, parsley, eggs, 1/2 C Parmesan, 1 tsp salt, and 1/4 tsp pepper.
Add spaghetti, beef, and onions. Stir to combine. Transfer to cake pan. Top with mozzarella and remaining Parmesan.
Bake for 25 to 30 minutes, or until cheese is bubbly and golden brown.
Cool for 5 minutes before serving.