Wash the potatoes and cook in boiling salted water for about 15 minutes. Peel and chop the onion. Heat oil in a pot and fry diced onion until transparent. Add milk and bring to the boil.
Roughly dice the gorgonzola and melt in the hot milk. If necessary, puree with the cutting stick of the hand mixer. Season to taste with salt, pepper and nutmeg. Meanwhile cut the bacon strips in half lengthwise.
Wrap 1 stalk of marjoram and 1/2 slice of bacon around the edges of each pork fillet medallion. Heat clarified butter in a pan. Fry the medallions for about 2 minutes on each side. Season with salt and pepper.
Wash the pear, dab dry, quarter, core and cut into slices. Grease casserole dish. Drain potatoes, quench, peel and slice. Layer about 2/3 of the potato slices in flaky layers.
Pour half of the gorgonzola sauce over it. Wrap the rest in potato slices, pear wedges and medallions. Spread the rest of the sauce on top. Bake in the preheated oven (electric cooker: 225 °C/ convection oven: 200 °C/ gas: level 4) for about 15 minutes.
Garnish with marjoram leaves before serving.