Preheat oven to 350. Spray 2 cookie sheets with nonstick spray.
Separate the whites from 3 of the eggs and discard the yolks. Put the remaining eggs and whites in a bowl and whisk until combined.
Drain the spinach, squeeze out the excess water and set aside.
Put the onion and garlic in food processor and pulseunil minced. Add the remaining ingredients, except for the bread crumbs. Pulse until combned. If you do not have a processor, make sure you finely chop the onions and garlic. Pour the mixture into a bowl. Add the breadcrumbs. Using your hands, mix together until well combined. Chill in the fridge for a minimum of 30 minutes. Form into balls, bout 3/4 -1 inch in diameter.
Bake on two greased cookie sheets for 12 minutes, turn over and bake another 8-10 minutes.