Pork Belly with Caviar

Make the pork belly: Combine salt, ground pepper, bell peppers, 3 cloves of the garlic, and bay leaf in a large bowl. Pack pork in salt mixture, cover, and refrigerate overnight. Uncover pork, rinse, and put into a small pot. Discard salt mixture. Cover pork with water. Add carrots, onions, celery leaf, cracked peppercorns, and remaining garlic and bring to a boil over medium heat. Reduce heat to medium-low and simmer, covered, for 5 hours. Transfer pork to a cutting board and set aside to let cool. Strain broth into a small pot, discarding solids, and set aside. Trim off rind and fatty top layer of pork, then cut pork into 4 pieces. Add pork to broth and keep warm over lowest heat.

Make the potatoes: Boil potatoes in a pot of salted water over medium-high heat until soft, 15–20 minutes. Drain, then pass through a potato ricer or a food mill into a sieve set over a medium bowl. Press potatoes through sieve. Stir milk and butter into potatoes and season to taste with salt and pepper. Cover with plastic wrap to keep warm.

Make the sauce: Heat oil in a small saucepan over medium heat. Add shallots and cook for 1 minute. Add wine and boil until almost evaporated, about 3 minutes. Add stock and bring to a simmer. Add butter, 1 tbsp. at a time, whisking thoroughly after each addition. Season to taste with salt and pepper. Strain sauce through a sieve into a medium bowl, then transfer to canister of "cream whipper".

To serve, divide potatoes between four warm bowls. Put one piece of pork in center of potatoes in each bowl, discarding broth. Following manufacturer's directions, aerate sauce in cream whipper into a small bowl. Spoon some of the foamed sauce around meat on each plate. Garnish meat with a spoonful of caviar and spoon a bit more caviar onto sauce.