Wash sole fillets, dab dry and sprinkle with lemon juice. Wash the apple, quarter it and cut out the core. Cut apple quarters into thin sticks. Clean, wash and cut leek into strips.
Cook the pasta in plenty of boiling salted water for about 10 minutes. Peel and halve the shallot. Bring slightly salted water to the boil. Add bay leaf and shallot. Leave sole fillets to simmer for about 5 minutes at low heat.
Heat butter. Steam apple and leek for about 3 minutes. Take out sole fillets and keep warm. Boil up 1/8 litre fish stock, white wine and cream. Bind with sauce thickener. Season to taste with salt and pepper.
Drain the pasta, let it drain. Arrange everything on plates and garnish with lemon wedges.