I cut the recipe in half and quite deliberately used a scale to weigh out 4 oz. meatballs, ending up with about 20 both times. Homemade meatballs deserve a homemade sauce, and I've used Hazan's famous recipe.
Greg's MEATBALL RECIPE
5# ground beef (80/20)
2# hot Italian sausage
2# sweet Italian sausage
1/4 C. garlic paste (in tubes at most grocery stores in produce section) (Kristine--made my own)
1/4 C. Italian herbs paste (in tubes at most grocery stores in produce section) (Kristine--made my own)
2 T. salt
2 T. black pepper
3/4 C. finely diced sweet yellow onion (Vidalia, Wala Wala) to name a few
1/4 C. finely chopped parsley
1/4 C. Heinz ketchup
4 Large eggs
2 C. finely chopped fresh sliced bread(1/8th in. dice) (sourdough, white or buttermilk acceptable. not flavored breads like Rye)
1/4 C. half & half
2# hot Italian sausage
2# sweet Italian sausage
1/4 C. garlic paste (in tubes at most grocery stores in produce section) (Kristine--made my own)
1/4 C. Italian herbs paste (in tubes at most grocery stores in produce section) (Kristine--made my own)
2 T. salt
2 T. black pepper
3/4 C. finely diced sweet yellow onion (Vidalia, Wala Wala) to name a few
1/4 C. finely chopped parsley
1/4 C. Heinz ketchup
4 Large eggs
2 C. finely chopped fresh sliced bread(1/8th in. dice) (sourdough, white or buttermilk acceptable. not flavored breads like Rye)
1/4 C. half & half

In a separate bowl, add finely chopped fresh bread with half and half. Mix and let soak in.
Then, in a larger bowl, add all other ingredients. Top with soaked bread mixture. Put on latex gloves and mix thoroughly by hand. Do not use power mixer. Do not overmix or over-handle meat mixture. This will make the meatballs tough. If you prefer a harder meatball, substitute 1 C. dry bread crumbs for the finely chopped fresh bread. Portion out meatballs to desired size. I use a kitchen scale to make sure each meatball is to exact portion size but this is not necessary. The more uniform they are the more evenly they'll cook. (See figure 1)

Place finished meatballs evenly on sheet pan. Bake for 5 min. @ 400 degrees for each meatball ounce. (5 oz. Meatballs will take 25 min.) You can broil on high for a few minutes to add a little color if desired. (See figure 2)
Once cooked, cool to room temperature.
Carefully rinse individual meatballs quickly under warm water to remove any excess grease. Place meatballs on paper towels and air dry. Once dry, they can be frozen in zip-lock freezer bags for later use.
Carefully rinse individual meatballs quickly under warm water to remove any excess grease. Place meatballs on paper towels and air dry. Once dry, they can be frozen in zip-lock freezer bags for later use.

The meatballs should be around medium rare after this cooking process. You finish cooking them completely once in the sauce.
If your meatballs are 2 oz.or smaller, place in large sauce pot and cover with sauce. Heat until hot, approx. 175°
If your meatballs are 3 oz. or larger, get a casserole dish large enough to hold your desired amount and fill half way with sauce. Place meatballs in sauce. The meatballs should be covered at least halfway. (See figure 3)
If your meatballs are 2 oz.or smaller, place in large sauce pot and cover with sauce. Heat until hot, approx. 175°
If your meatballs are 3 oz. or larger, get a casserole dish large enough to hold your desired amount and fill half way with sauce. Place meatballs in sauce. The meatballs should be covered at least halfway. (See figure 3)
Bake at 400° until thoroughly hot. Approximately 25 to 45 min. depending on the size you made your meatballs. Once hot, remove from oven and top with generous portions of shredded mozzarella, Provolone and top with Pecorino Romano. Broil on high until Brown and bubbly. (See figure 4) Top with fresh chopped parsley for color contrast. Serve over pasta or in a crusty sweet French roll for an incredible meatball sandwich. Enjoy!!!
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Because it was a new recipe with several steps, the first time I made them, it was a bit daunting. The second time, even though it was a year later, went much more quickly. It fed the four of us as a main dish (no pasta included!), and I froze half the batch to use later.
These are my completed meatballs. And Greg was right--they are absolutely amazing!