What is a crumble?
A crumble is a fruit-based dessert with a crumbly topping called a streusel that's a mixture of flour, butter and sugar -- plus optional flavorings like cinnamon, vanilla extract, lemon zest or nuts -- that is baked until crisp. The flour, butter and sugar are combined until they form crumbs; some people like to add oats or nuts to the mixture.
Apple crumble is traditional, but you can make a crumble out of rhubarb, blackberries, plums or just about any fruit. A crumble is delicious warm or cold, plain or accompanied by a scoop of vanilla ice cream, heavy cream or custard.
The crumble is said to have been invented in Britain during World War II, when food rationing made pie crusts an impossibility. Americans sometimes call the crumble a crisp.