Heat oven to 425° F. If using a cast iron skillet, place it in the oven to preheat.
In a small food processor (or by hand) chop garlic, onion, and herbs (if using fresh) until they are finely minced.
Add mixture to a large bowl with the rest of the ingredients except for oil. Mix until all of the ingredients are distributed evenly. I like to use my hands to squish it all together.
Roll mixture into meatballs that are about 2 inches in diameter.
Use olive oil to carefully coat the bottom of the hot cast iron skillet.
Place meatballs about 1 inch apart and bake until the center is cooked through (it should register at 155° F on a thermometer), about 20 minutes.
If you prefer a crispy outside, you can broil meatballs for 5 minutes or so, watching them carefully.
Remove from oven and enjoy over pasta or zucchini noodles with your favorite sauce.
