Preheat the oven to 210°C.
Season the pork fillet and brush it with honey.
Heat a frying pan and add 25g of butter.
Sear the pork on all sides until golden brown.
Roast the pork in the oven for 8-10 minutes until cooked through.
Remove the pork from the oven and rest for five minutes.
Grate the potatoes and apple onto a tea towel.
Squeeze the tea towel to remove all water and starch.
Mix the potato and apple with crème fraîche and egg yolks in a bowl.
Fill an 8cm chefs' ring halfway with the mixture and add a prune.
Fill the rest of the ring with potato mixture and press firmly.
Fry the rösti in 25g of butter for 2-3 minutes per side until crisp.
Serve the rösti with the sliced pork fillet.