Trim and cut the Pork Shoulder, Pork Belly and Pork Back Fat into roughly 1-inch cubes so they cook evenly.
Season the pieces generously with Sea Salt and freshly ground Black Pepper.
Place the seasoned meat in a heavy Dutch oven or deep saucepan and add smashed cloves of Garlic, one or two Bay Leaf, and a few sprigs of Thyme.
Pour in enough Water to come about halfway up the meat, then stir in a few tablespoons of Pork Lard to enrich the braising liquid.
Bring to a gentle simmer over low heat, cover partially, and cook very slowly for 2 to 3 hours until the meat is meltingly tender and easily pulls apart with a fork (you can also braise in a 275°F/135°C oven).
Remove the meat from the pot, discard the Bay Leaf and thyme stems, and reserve the cooking liquid and fat. Let the meat cool slightly, then shred it with two forks or by hand into bite-sized strands.
Return the shredded meat to a bowl and fold in enough of the reserved fat and a few spoonfuls of the strained cooking liquid to achieve a spreadable, cohesive texture. Taste and adjust seasoning with more Sea Salt and Black Pepper if needed.
Pack the rillettes firmly into a jar or shallow terrine, smoothing the surface. Melt a little more Pork Lard and pour a thin layer over the top to seal, then cool to room temperature and refrigerate for several hours or overnight to set.
Serve the rillettes spread on slices of crusty Baguette with sharp, vinegary Cornichons on the side to cut the richness.
