Eggs Benedict on Spartan apple and old cheddar rösti

Preparation

For rösti

1. In a mixing bowl, combine the grated apples, grated potatoes, cheddar cheese and melted butter.
2. Season with salt and pepper
3. Using a 3½" (7.5 cm) diameter cookie cutter, form tightly packed patties about ¾" (2 cm) thick on a parchment-lined baking sheet.
4. Bake in a preheated oven at 450°F for 15 minutes.
5. Reduce oven temperature to 350°F and continue cooking for 15 minutes.
6. Book

For the sauce

1. Pour the water, lemon juice and egg yolks into a mixing bowl.
2. Place in a bain-marie and whisk vigorously until the yolks thicken (be careful, it can quickly become an omelette).
3. Remove from heat and continue whisking, incorporating the butter drop by drop without ever stopping (like a mayonnaise).
4. Stir in the ice cider and season with salt and pepper, then set aside.
5. Just before serving, return to the bain-marie for a few moments and whisk again to loosen the sauce.

For poached eggs

1. In a saucepan with about 2 liters of simmering water, add the vinegar.
2. Stir the water to create a whirlpool, then plunge the eggs into it.
3. Cook for 2 ½ to 3 minutes
4. Remove with a slotted spoon and place on absorbent paper.

For assembly

1. Place on each plate, in order: a rösti, a slice of prosciutto and a poached egg.
2. Top with sauce and garnish with chives
3. Serve