Cook the meatballs according to package instructions. Remove from the oven and reserve warm.
Heat the oven to 400ºF.
Melt the butter in a saucepan with half of the garlic.
Split the loaf lengthwise and spread the garlic over each half.
Place the halves, butter side up, on a sheet pan and place in the oven until golden brown.
While meatballs are cooking, combine the other half of the garlic along with the shallots, parsley, basil, anchovy paste, capers, oregano, crushed red pepper, and vinegar in a food processor bowl.
While processing the mixture on high, drizzle in the olive oil until a slightly chunky sauce forms. Transfer to a jar or bowl for serving.
When bread is done, slice the meatballs into three slices, cut or tear the bread into chunks, and place both on a platter with the salsa verde on the side.
Guests can slather the salsa verde on a chunk of bread, top with some slices of meatballs and slices of ricotta salata.