Melt the butter and stir in the Strattu di pomodoro, freshly chopped shallot and pesto verde. Add the flour. Cook the roux and add the chilled vegetable stock while stirring to make a smooth ragout. Season the ragout with salt and pepper and allow to cool. Shape the ragout into croquettes and freeze them. Roll the croquettes in the egg and breadcrumbs. Mix the mayonnaise with the pesto di basilico. Cut the slices of bread down to size so that you can roll the croquettes in them. Fry the croquettes at 175 ⁰C until they are golden-brown. Spread the pesto-mayonnaise on the bread and roll the croquettes tightly in it. Slice the croquettes diagonally. Garnish the croquettes with suitable cress.