Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.
In a large mixing bowl, combine ground chicken, ricotta cheese, Parmesan cheese, egg, breadcrumbs, garlic, oregano, salt, black pepper, and red pepper flakes (if using).
Mix gently until all ingredients are incorporated, being careful not to overmix.
Using a spoon or hands, form the mixture into meatballs about 1 1/2 inches in diameter and place them on the prepared baking sheet.
Bake for 18-20 minutes, or until meatballs are golden and cooked through (internal temperature of 165°F/75°C).
Optional: For extra browning, heat olive oil in a skillet over medium heat and sear the meatballs for 2 minutes on each side after baking.
Serve with marinara sauce, pasta, or as a meatball sub.
Notes
For a lighter version, use part-skim ricotta. You can also add chopped fresh basil or parsley for extra flavor.