Old-fashioned Rhubarb Crisp is a sweet and tangy taste of nostalgia. Made with farm stand rhubarb, hearty oats, brown sugar and cinnamon, this cast iron skillet recipe is simple and scrumptious.
Preheat oven to 375 degrees. Grease the bottom and sides of a 9-inch cast iron skillet then set aside.
Place rhubarb and sugar in a medium-sized bowl. Stir to combine then set aside for 15 minutes.
Using a slotted spoon, transfer rhubarb to the cast iron skillet. Discard any excess liquid left in the filling bowl.
Add lemon juice, cornstarch and vanilla to skillet. Stir until evenly combined with rhubarb.
Crisp Topping
Add all topping ingredients to a medium-size bowl. Cut in butter with two forks until the mixture is crumbly and the butter is pea-sized.
Sprinkle topping over rhubarb filling in an even layer then bake for 35 to 40 minutes or until topping is golden brown and fruit juices are bubbly hot.
Remove skillet from oven and cool for 10 minutes to allow juices time to thicken. Serve warm with a scoop of vanilla ice cream.
To store, cool leftovers to room temperature then cover refrigerate up to 5 days.