Make the sauce: Heat the olive oil in a large pot over medium heat. Add the onion and 2 teaspoons salt; cook, stirring, until soft, about 5 minutes. Stir in the tomato paste and cook, stirring, until the oil is red, 2 to 3 minutes. Add the pork and red pepper flakes and cook, stirring, until the meat is cooked through, about 10 minutes.
Add the crushed tomatoes and their juices and 1 cup water to the pot. Bring to a boil, then reduce the heat and simmer, stirring occasionally, until the sauce is reduced by one-third, about 1 hour.
Meanwhile, make the meatballs: Preheat the oven to 450 degrees F. Mix the ground pork, 1 tablespoon salt, the cherry peppers and their pickling liquid, the bread and eggs with your hands until combined. Roll into 24 golf ball-size meatballs.
Coat a rimmed baking sheet with the olive oil, then put the meatballs on it and bake until firm and cooked through, about 14 minutes; let cool 5 minutes on the baking sheet.
Divide the meatballs among bowls and top with the sauce. Serve with polenta, if desired.
Recipe courtesy Daniel Holzman and Michael Chernow for Food Network Magazine