Remove the first thin skin from the onions (they should be fairly large and all about the same size), place them on an oven tray covered with a sheet of foil and cook in a preheated oven, at 180 °C, for about 45 minutes. When they’re soft and a little “deflated”, remove them from the oven, peel off the first layer of skin again and cut them into small pieces with a sharp knife. Place the pieces on a plate and grind some black pepper over them. Toast the slices of bread (you can use the oven, which is already hot, by putting them in it when you take the onions out) and, when they begin to brown, remove them and spread them immediately with the honey (half a tablespoon per slice). Put some pieces of onion and thin slivers of pecorino on each slice and serve the “crostoni” (= large crostini) immediately, while still slightly warm.