Preheat the oven to 200 degrees. Line the baking sheet with parchment paper.
Mix everything except the feta cubes, form portions with a heaping tablespoon, press the feta cubes into the middle. Makes approx. 20 meatballs = 1 tray with 4 rows of 5 meatballs. Sizzle for 20 minutes on the middle rack at 200 degrees circulating air. Cook in another 10 minutes with the grill switched on.