Sterilise the oyster shells by thoroughly washing them in hot, soapy water. Once they are dry, put them onto a large baking sheet. Put a teaspoon of pesto into each shell and sprinkle over some salt and a teaspoon of breadcrumbs. Top each oyster shell with a bocconcini ball, split in half, another spoonful of pesto, a cherry tomato and a glug of olive oil.
Place them under a hot grill until the cheese has melted. Put them onto a plate and serve immediately.