Tart-N-Sweet Rhubarb Crisp

2 ½ cups quick cooking oats

2 ½ cups brown sugar

3 cups all-purpose flour

⅓ cup butter, melted

9 cups chopped rhubarb

3 teaspoons ground cinnamon

2 cups water

2 cups white sugar

¼ cup cornstarch

2 teaspoons vanilla extract

Preheat oven to 350 degrees F (175 degrees C). Grease a 9x13 inch baking dish.

In a large bowl, mix together oats, brown sugar, flour and butter. Put half of the mixture into the bottom of the baking dish. Place rhubarb over top of mixture and sprinkle with cinnamon.

In a medium saucepan, cook water, sugar, cornstarch and vanilla over medium heat until thick; let cool slightly. Pour over rhubarb and sprinkle remaining oat and flour mixture on top. Bake in preheated oven for 30 to 35 minutes.