I had already made compote and a pie; here is a third way to cook the rhubarb. The crumble is really easy to do. Slightly acid, it's great.
Ingredients (for 4 people)
500 g rhubarb
1 or 2 sweet apples
90 g warmed butter
125 g flour
60 g brown sugar
1 sachet vanilia sugar
Pre-heat the oven at 210°.
Wash, peel and cut the rhubarb in cubes, do the same for the apple. Put the fruits in a gratin dish and sprinkle with vanilia sugar.
With your fingers, bring together the flour, the butter and the brown sugar. Pour on the fruits.
Bake for 25-30 min (brown the top during the last 5 minutes).