Heat oven to 375°F. Line four baking sheets with aluminum foil for easy clean up and set aside. For even easier baking, use disposable aluminum baking pans.
Place the ground beef in a very large mixing bowl. In a second smaller bowl, combine the remaining ingredients. Stir together (best to just mix really well with your hands) until bread is completely broken up and a soft, liquid-y mixture forms. Add the mixture to the ground beef and work together with your hands until very evenly combined.
Shape beef mixture into 2-inch sized meatballs (mixture should make about 64 meatballs) and place on baking sheets, about 16 meatballs per baking sheet.
Bake 15 minutes or until meatballs are cooked through and no pink remains. Remove from oven and cool meatballs on baking sheets until they are room temperature.
Place cooled meatballs on baking sheets in the freezer and freeze for 4 hours or until frozen solid. Place frozen meatballs in a plastic zip-top freezer bag and store up to six months.
To reheat, place meatballs on baking sheet and bake for 15 to 20 minutes at 350°F or until heated through. Or, thaw in the refrigerator and place in hot marinara on the stovetop; cook until heated through.
Recipe by Espresso and Cream at https://www.espressoandcream.com/2017/02/freezer-meals-new-moms-meatballs.html