Preheat oven (electric cooker: 80 °C/circulating air: not suitable/gas: see manufacturer). Pat the steaks dry and wrap each with 1 slice of bacon. Tie with kitchen string. Heat lard in a pan. Sauté the steaks in it for about 1 minute on each side. Season with salt and pepper. Roast in the oven for about 1 hour. Keep the pan with the frying set.
In the meantime peel the shallots and dice them finely. Wash the basil, shake dry and pluck the leaves. Boil up wine, vinegar, half of the shallots, peppercorns and about 8 basil leaves in a small pot. Simmer for 2-3 minutes until the liquid is reduced to 1/3 (3-4 tbsp). Pour through a fine sieve and allow to cool.
Cover the beans and steam them for 12-15 minutes in a little boiling salted water. Put polenta for the dumplings in a deep plate. Form 12 small oval dumplings (type gnocchi) from the dumpling dough and turn them in the polenta. Heat 3 tablespoons of butter in a coated pan. Fry the dumplings in it until golden brown all around.
Drain the beans on a sieve. Heat 1 tbsp. butter in the pot, fry the remaining shallots in it. Add beans and lemon peel and toss. Season to taste with salt and pepper. Keep warm.
For the sauce, cut the remaining basil leaves into strips. Melt 150 g butter. Whisk egg yolks and reduced wine in a hot water bath for 5-8 minutes until thick and creamy. Add warm liquid butter, first drop by drop, then in a thin stream, stirring constantly. Stir in basil. Season to taste with salt and pepper. Heat the frying set in the pan. Briefly fry the medallions on the bacon side all around. Arrange everything.