For the roast pork, score the rind crosswise with a knife. Finely crush the peeled garlic with salt, peppercorns, pumpkin seeds and cloves in a mortar. Stir in the oil and rosemary.
Rub the meat with the spice mixture. Pour finger-high boiling salted water into a roasting pan. Place the roast in the roaster with the rind facing downwards and place the roaster on the lowest shelf in the oven preheated to 225 °C. Cook for about 15 minutes.
Cook for about 15 minutes, then turn the meat and cook for another 15 minutes with the rind facing up.
Slice the carrots and add them to the roaster together with the bay leaf. Pour beer over the meat and braise for another 45 minutes. Baste the rind frequently with the gravy.
Clean the leeks, wash them and cut them into 5 cm long pieces. Reduce the heat in the oven to 175 °C. Spread the leek pieces around the meat and pour soup over them.
Place the roaster on a higher shelf in the oven, roast for another 45 minutes. Keep basting with juices. Remove the roast and leek pieces and keep warm in the turned off tube.
Puree the sauce, season with salt and pepper.