For the best results, make this recipe a day or two in advance. Slice off the top of the loaf and reserve to use as a lid. Using a grapefruit knife, cut out the centre of the bread, leaving a hollow shell 1-2 cm thick. Turn the bread you have taken out into crumbs using a food processor. Put half the crumbs back in the processor with the pesto and blitz, then blitz the remaining crumbs with the French dressing. Layer the ingredients into the bread shell in the following order: two thirds of the pesto mixture, salami, sliced tomato, black olives, the French dressing crumb mixture, prosciutto, herbs, chillies or peppers, and finally the remainder of the pesto crumbs. Make sure that everything is packed evenly and press the fillings down firmly with your hands. Replace the bread lid and set the loaf on the square of muslin.
Tie two opposite corners of the fabric tightly together and repeat with the remaining two corners so that the muslin is taut. Place a weight on the loaf and chill at least overnight. To serve, unwrap and slice into wedges.