Strawberry Rhubarb Bars with Oats

Instructions:

1. Line a 9x9 inch baking pan with parchment paper, creating a sling overhang on two sides for easy removal.
2. In a large bowl, combine flour, oats, sugar, and salt. Cut in the cold butter using a pastry cutter or forks until the mixture resembles coarse crumbs.
3. Stir in the vanilla extract. Press 2/3 of the crumble mixture firmly into the bottom of the prepared pan.
4. Pre-bake the crust at 350°F (175°C) for 8 minutes to create a moisture barrier.
5. In a separate bowl, toss the diced strawberries and rhubarb with lemon juice and ground cinnamon.
6. Stir in the sugar and cornstarch until the fruit is evenly coated.
7. Spread the fruit mixture evenly over the pre-baked crust, smoothing it to the edges with a spatula.
8. Sprinkle the remaining 1/3 of the crumble mixture evenly over the fruit layer.
9. Bake for 45-55 minutes until the topping is golden brown and the filling is bubbling.
10. Allow the bars to cool completely in the pan for 2 hours before lifting the parchment sling to slice into squares.