1. With the ingredients from Group 1:
   1. Shred the bread into small pieces in a large bowl, then add the buttermilk and heavy cream.
   2. Use a spatula to work the mixture into a paste. It may help to allow the mixture to sit for a few minutes before "smushing."
2. With the ingredients from Group 2:
   1. Heat the olive oil in a sauté pan over medium-low heat. Add the shallot and cook until softened and just beginning to brown, stirring often.
   2. Add the garlic and pine nuts and continue to cook, stirring constantly until the garlic becomes fragrant.
   3. Turn the heat off then add the wine. Stir to deglaze the pan.
   4. Allow the mixture to cool.
3. With the mixture from Step 2 and ingredients from Group 3:
   1. Transfer mixture from Step 2 and all ingredients to the bowl of a food processor.
   2. Process until the mixture is finely-ground and begins to clump/ball, similar to a dough's behavior in the food processor.
   3. Transfer to the bowl with the mixture from Step 1. Stir well to combine the two into a homogeneous paste.
4. With the mixture from Step 3 and ingredients from Group 4:
   1. Break the ground meats into smaller clumps and add to the bowl along with the lemon zest.
   2. Begin by tossing without breaking-up the meat clumps.
   3. Once the paste has been well-distributed, begin "smushing" until all is just barely homogenized.
5. Cover with plastic wrap and refrigerate overnight.

To par-cook the meatballs:

1. Heat the oven to roast at 425 °F.
2. Portion the mixture into 16 to 18 meatballs on a parchment-lined rimmed sheet pan.
3. Roast until the meatballs reach 140 °F.
4. Switch the oven to broil. Once the tops of the meatballs take on some darker color and the internal temperature has reached 150 °F, remove from the oven.

At this point the meatballs could be packed and refrigerated or frozen. For service:

1. Empty a quart of tomato sauce into a large saute pan and arrange the meatballs in the sauce.
2. Cover the pan with a lid and place over medium-low heat.
3. Once sauce is bubbling, continue to simmer for 5 minutes.
4. The finished internal temperature should be 165 °F.

Top with sauce and grated parmesan or serve in a steak roll.