Pour the milk on the sour dough bread.
Let it sit for 2-3 minutes then with your hands tear the sourdough into very small chunks.
Grate onion and zucchini, squeeze them really hard after you grate them so all the water comes out. You don’t need the water for meatballs.
Mix ground turkey, sourdough, and grated onion and zucchini in a bowl with your hand until combined.
Add the egg, barbecue sauce and spices. Mix again.
Cover the bowl and put it in the fridge for 30 minutes.
Preheat the oven to 400F/204C.
Line a baking sheet with foil and spray it with non stick spray.
Take the mixture out of the fridge, using an ice cream scoop, make scoops of the turkey mixture and place them on the baking sheet.
Bake the meat balls in the oven for 25 minutes, turn on broil for 2-3 minutes so they get color on top.