1 cup all-purpose flour
3/4 cup rolled oats
1 cup brown sugar
1 1/2 teaspoon ground cinnamon
1/2 cup butter, melted
3 cups peeled, cored and sliced apples
1 cup chopped rhubarb (or strawberries)
1/2 cup white sugar
1 Tablespoon cornstarch
1/2 cup water
1/2 teaspoon vanilla extract
Preheat oven to 350 degrees F (175 degrees C). In a medium bowl, combine flour, oats, brown sugar, cinnamon and melted butter. Stir until crumbly.
In a medium saucepan, combine white sugar, cornstarch, water and vanilla and rhubarb. Cook, stirring, until thick and clear, 10 minutes.
Put apples in bottom of 9x13 pan. Pour the rhubarb-sugar mixture over it. Cover fruit with crumble mixture. Bake in preheated oven 45 minutes, until bubbly and golden. Serve with ice cream and/or whipped cream.