Preheat oven to 425°.
Combine rhubarb, sugar, vanilla and lemon juice in a large bowl. Set aside.
In a separate bowl, combine light brown sugar, flour, oats and salt. Cut in butter with a pastry cutter or fork (or fingers) until mixture is crumbly. Refrigerate 10–15 minutes.
Divide rhubarb in individual oven-safe ramekins, or arrange in a medium-sized baking dish. Loosely sprinkle the crumble over the top. Bake for 25–30 minutes, or until browned and slightly crispy. Cool for 10 minutes. Serve with a scoop fresh mint ice cream on top.
Recipe by Christopher Bender and David Crowell, Chef/Owners, Stoneacre Pantry, Newport