Using a serrated knife, cut a 1/2 inch grid patter about three quarters of the way into the bread, taking care not to cut all the way through. Mix the prosciutto, cherry tomatoes, garlic, and havarti in a bowl. Pour the melted butter over the mixture and combine. Using your hands, stuff the crevices of the bread. Stack 4 sheets of heavy duty aluminum foil large enough to cover the stuffed loaf of bread. Wrap the foil around the loaf, making sure the edges are sealed. Place the wrapped loaf in the fire on top of the hot coals and bake for 10-15 minutes. Make sure to rotate the loaf so that it does not burn. You may need to add extra time, depending on how hot your coals are. Once the cheese has melted, remove the loaf from the fire and allow to cool slightly. Serve warm.