Peel, wash and chop the celery and potatoes. Cook in boiling salted water for about 20 minutes. Peel beetroot and slice it very thinly. Peel, quarter and core apples, also slice them into thin slices. For the dressing, whisk vinegar with honey, salt, pepper and 2 tsp. lemon peel. Fold in sunflower oil in a thin stream. Mix dressing with beetroot and apples. Let stand for about 15 minutes
Wash herbs, shake dry. Pluck off leaves and chop finely, except for a little thyme for garnishing. Peel garlic and chop finely. Mix breadcrumbs with herbs, garlic and 1 tsp. lemon peel. Wash the monkfish fillets and dab dry. Sprinkle fish with half of the lemon juice, season with salt and pepper and roll in the breadcrumbs. Heat olive oil in a frying pan and fry the fillets over medium heat for 5-7 minutes until golden brown, turning them over.
Heat 250 g cream in a pot, melt 25 g butter in it. Drain potatoes and celery, press through the potato ricer. Add the cream mixture and mix. Season to taste with salt, pepper and nutmeg. Peel ginger and grate finely. Bring 150 g cream, stock and ginger to the boil in a saucepan and let it simmer a little bit. Season to taste with remaining lemon juice, salt and pepper. Stir in 25 g butter in flakes and foam up with a hand blender. Season beetroot salad once again. Serve fish with sauce, puree and salad. Garnish with set aside thyme and lemon wedges