Wash, peel and chop the potatoes. Cook in boiling salted water for about 20 minutes. Wash and clean the beans. Cook in little boiling salted water for 15-20 minutes. Warm up milk and 25 g butter.
Drain the potatoes and let them steam briefly. Add milk and butter, mash to a puree, season to taste with salt and nutmeg. Drain the beans, rinse with cold water and drain well. Wash the thyme, dab dry, put something aside for garnishing.
Finely chop the rest. Crumble bread in the universal chopper. Melt 100 g butter in a pan. Roast bread in it until golden brown. Add thyme and roast briefly. Spread the puree in 4 small or 1 large casserole dish.
Wrap the beans with the ham in portions to make 12 packets. Place on the puree. Spread the butter and breadcrumbs mixture over the packs. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-15 minutes.
Garnish with thyme put aside.