Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper for easy cleanup.
In a large mixing bowl, combine the ricotta cheese, ground beef, breadcrumbs, Parmesan cheese, egg, minced garlic, oregano, salt, black pepper, and red pepper flakes (if using).
Mix all the ingredients gently until just combined; be careful not to overmix as this will lead to tough meatballs.
Using your hands, shape the mixture into golf ball-sized meatballs and place them on the lined baking sheet. Aim for about 20 meatballs.
Bake for 20-25 minutes, or until the meatballs are cooked through and a golden-brown crust has formed on the outside.
While the meatballs are baking, simmer the marinara sauce in a pan over low heat.
Once the meatballs are done, gently transfer them to the simmering marinara sauce and let them cook for an additional 5-10 minutes to soak up the flavors.
Serve hot, garnished with fresh basil leaves.
Notes
Serve over spaghetti with extra marinara and Parmesan for a delightful presentation.