Prep. Preheat oven to 400 F and line 2 baking sheets with parchment paper.
Food processor. Toss onion (1) and garlic (6 cloves) in a food processor and pulse using 1 second intervals. You'll want to pause the processor and scrape down the sides occasionally to incorporate everything. When the onion is "minced" add the parsley and continue to pulse everything together until everything is minced.
Combine + shape. Add parlsey (1/2 cup), onion and garlic to a large bowl together with the beef (2 pounds), pepper (1 teaspoon), salt (2 teaspoons), cumin (2 teaspoons), oregano (2 teaspoons), and cinnamon (1/4 teaspoons), and combine using your hands. Shape into 32 golf ball sized meatballs.
Whipped feta. Meanwhile, make the feta by blending everything together in a food processor until creamy and smooth. Make sure to crumble the feta into small pieces before processing. This will take 5+ minutes, depending on your food processor. To save time you can use room temp cream cheese and feta!
Bake in the preheated oven until cooked through, about 18-22 minutes.
Notes
Beef - 80/20 is key for juicy meatballs.
Nutritional information is for 4 meatballs, not including the feta, if you make 32 meatballs: