Crostini are small pieces of bread toasted In the oven. Making crostini is a good way of using stale bread. Stale bread is easier to slice and it also toasts more quickly. Brush pieces of bread cut into quarters with olive oil on both sides. Toast in the oven until crisp (350 °F/ 180 °C). Spoon your choice of topping while still hot and serve. Crostini keeps well in an airtight container for a couple of days. If they are kept too long the oil becomes stale. Place in a heated oven for 10 minutes to crisp them up before spooning on your choice of topping.