On a work surface, rub the salt mixture over the whole roast. Wrap in the pork fat, without covering the bones. Using butcher’s twine, tightly tie between each bone. Remove any excess twine. Sprinkle the fat with the fleur de sel. Place the meat in a roasting pan, fat side up. Leave at room temperature for 1 hour.
Meanwhile, with the rack in the middle position, preheat the oven to 500°F (260°C).
Layer two large sheets of aluminum foil. In the centre, place the onions and garlic bulb. Drizzle with the oil. Tightly seal and place in the pan beside the roast.
Roast for 35 minutes, then turn off the oven. Leave the roast inside and keep the oven door closed for 1 hour and 30 minutes and up to 2 hours.
Meanwhile, in a saucepan over high heat, bring the wine to a boil and redure for 5 minutes. Add the broth and let reduce by half. Cover and set aside until the meat has finished cooking.
Add the roasted onions and crushed garlic bulb to the wine mixture. Bring to a boil, then simmer for 10 minutes. Strain through a sieve. Season with salt and pepper.
Horseradish Cream Sauce
When ready to serve, combine the cream and horseradish. Season with salt and pepper. Slice the roast and serve with the wine sauce and horseradish cream sauce.
Note from Ricardo
Ask your butcher for a piece of pork fat for barding (when fat is placed on meat before roasting). It is rarely found in the meat aisle, but should be available upon request.
