Preheat oven to 400°F. Line two large baking sheets with parchment paper or spray with cooking spray.
In a large mixing bowl, combine ground beef, breadcrumbs, Parmesan cheese, eggs, garlic, grated onion, Italian seasoning, garlic powder, salt, and pepper. Gently mix until just combined—do not overmix.
2 lbs ground beef, 1 cup breadcrumbs, 1 cup grated Parmesan cheese, 2 large eggs, 1/2 cluster garlic, 1/2 medium onion, 1/2 tbsp dried Italian seasoning, 1/2 tbsp garlic powder, 1/2 tsp salt, 1/2 tsp black pepper
Shape into 1.5-inch meatballs (approximately 32 meatballs) and place them on the baking sheets.
Bake meatballs in the preheated oven for 20 minutes, or until cooked through and slightly browned.
While the meatballs bake, heat olive oil in a large skillet over medium heat. Add minced garlic and sauté for 1-2 minutes until fragrant.
2 tbsp olive oil, 1/2 cluster garlic
Stir in marinara sauce and dried basil (if using). Simmer on low heat for 5-10 minutes.
24 oz marinara sauce, 1/2 tbsp dried basil
While the sauce simmers, cook the spaghetti according to package instructions. Drain and toss with olive oil to prevent sticking.
8 oz spaghetti or pasta of choice, 1 tbsp olive oil
Once the meatballs are baked, transfer them to the skillet with the marinara sauce. Toss gently to coat the meatballs in the sauce.
Divide the pasta into meal prep containers or plates. Top with the sauced meatballs and garnish with parsley if desired.
1/4 cup chopped fresh parsley