Wrapped Roast Monkfish with Champagne Sauce

Name: Wrapped Roast Monkfish with Champagne Sauce
Ingredients: 1 learn monkfish tail (1.25-1.5kg), skinned and filleted to give 2 x 400-500g fillets; 2 tbsp. olive oil, plus extra to drizzle; 2 tbsp. finely chopped fresh dill, plus extra to scatter; Finely grated zest 1/2 lemon; 6 -8 Parma ham slices; 2 medium onions, halved and thinly sliced; 2 garlic cloves; 2 bay leaves; 300 mL hot chicken or vegetable stock; 25 g butter; 1 echalion shallot, finely chopped; 400 mL Champagne; 200 mL double cream; 2 tbsp. baby (non-pareille) capers, drained; 1/2 -1tsp sugar, to taste; Kitchen string