Peel, wash and cut the potatoes into large pieces. Cover and cook in salted water for about 15 minutes. Roast mustard seeds in a pan without fat for 1-2 minutes, putting a lid on them as soon as the grains start to crack.
Take out and let it cool down.
Peel, wash and cut the carrots into pieces. Onions peel, in fine columns cut. Drain the potatoes and put them with the carrots and onions in an ovenproof dish. Mix starch with 2 tablespoons of water.
Dissolve the stock in 1⁄2 l warm water, mix with the starch. Season with pepper and nutmeg. Pour over the vegetables.
Mix mustard and mustard seed, season with salt. Dab meat dry and brush with the mustard mix. Place on the vegetables. Close the mould tightly with a lid or aluminium foil. Bake in a hot oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see
manufacturer) cook for 30-35 minutes.
Wash the herbs, shake dry and chop or cut into small rolls. Take the meat out, roll in the herbs and cut into slices. Arrange vegetables, meat and stock.