Season the shoulder of pork with salt and pepper.
In a heavy bottom saucepan large enough to snugly fit the pork shoulder, melt 50g butter and allow to foam.
Add the shoulder fat side down and slowly cook until golden and the fat has rendered, approximately 10 minutes maximum. Turn the pork and colour the other side.
Remove the meat from the pan, drain off the excess fat and wipe clean.
Place the remaining butter into the pan and melt. When foaming add the sage and garlic, cook gently for 1 minute. Then add the lemon, cook gently for a minute and then add the pork fat side up.
Pour enough milk into the pot to bring the level up to ½ the height of the pork. Bring the milk to a simmer and then place a loose cover of wet baking paper over the top so as the moisture is maintained over the pork but the liquid can evaporate. Place in a static oven at 150°C.
Cook like this until the liquid reduces then turn over and add the same amount of milk again and repeat the process. The meat when cook should be very tender and the milk will have reduced and coagulated.
Serve with braised fennel or cavalo nero.