01 -
Preheat oven to 350°F and line a 9x13 inch baking dish with parchment paper for easy removal.
02 -
Combine flour, oats, brown sugar, and melted butter in a bowl. Mix until moistened and press evenly into the prepared pan.
03 -
Bake crust for 15 minutes until dry and set but not browned. Remove from oven and set aside.
04 -
In a saucepan over medium heat, cook rhubarb, granulated sugar, and cornstarch while stirring until thickened and rhubarb is soft, about 6 minutes. Stir in vanilla and remove from heat.
05 -
Pour rhubarb mixture over the baked crust and spread evenly. Bake for another 10–15 minutes until set and glossy.
06 -
Beat cream cheese, powdered sugar, and vanilla until smooth and fluffy using an electric mixer.
07 -
After bars cool completely, spread cream cheese topping evenly over the surface. Chill in the refrigerator for at least 2 hours.
08 -
Cut chilled bars into squares with a clean knife dipped in hot water. Serve cold for best texture.