Petit sale, or salted pork (not to be confused with salt pork), readily available at charcuteries in France, is a rarity in this country—so when we needed some for our bistro-style Petit Sale Aux Pommes De Terre, we decided to make our own. We found a recipe for curing pigs' feet in Jacques Pepin's The Art of Cooking, Volume II (Knopf, 1988), and adapted it to the purpose. Mix together 2 cups kosher salt, 1/2 cup sugar, 2 tbsp. cracked black pepper, 1 tsp. saltpeter, and 1/2 tsp. dried thyme leaves in a medium bowl and set aside. Rinse a total of 5 lbs. of pork shoulder and pork loin ribs, with chine (backbone) cracked, under cold water, then pat dry. Add meat to a large deep bowl or pot. Rub prepared salt into meat (most will dissolve into a salty brine as meat cures). Cover bowl or pot with plastic wrap and refrigerate for 4 days, turning meat and rubbing it with undissolved salt and brine several times a day, then rinse meat and cook as your recipe directs.