Gratins with asparagus and antiboise

Ingredients

• 8 Aviko Gratins tomato mozzarella
• 3 tomatoes
• 1 tbsp pine nuts
• 500 g green asparagus
• 100 ml olive oil
• 100 ml tarragon vinegar
• 1 shallot, finely chopped
• 2 white peppercorns, bruised
• 250 g unsalted butter
• ½ onion, finely chopped
• 1 clove of garlic, finely chopped
• 1 tbsp capers
• 25 g black olives, ringed
• 2 tbsp finely chopped parsley
• 1 egg
• 1 egg yolk
• 2 tarragon sprigs, leaves only
• 12 slices of Parma ham