Preheat the oven to 400 degrees F (200 degrees C or gas 6).
Using your fingers, rub together the flour, butter, and the rest of the sugar (you can also do this in a food processor?just blitz until the mixture resembles fine breadcrumbs). I prefer to do this by hand as I like to end up with a nice rustic-looking crumble?with some bits bigger than others.
Put the fruit into an ovenproof serving dish or into individual dishes. Sprinkle the crumble mix over the fruit, making sure to pile more into the middle of the dish. Bake it in the oven for about 30 minutes, or until the middle of the crumble is evenly golden and the fruit has started to bubble up around the edges.