📖 Instructions

1. Preheat the Oven: Set your oven to 375°F (190°C). Making sure your oven is properly preheated will make a big difference in how evenly your crust bakes.
2. Prepare the Rhubarb: Wash 1 pound (about 4 cups chopped) of fresh rhubarb stalks. Trim the ends and chop the stalks into 1/2-inch pieces. Don't worry too much about uniformity; a little variation adds character.
3. Make the Crust: In a large bowl, whisk together 2 1/2 cups all-purpose flour, 1/2 cup granulated sugar, and 1/4 teaspoon salt. Ensuring these dry ingredients are well-combined helps distribute the sweetness and saltiness evenly throughout the crust. I sometimes sift the flour to avoid clumps.
4. Add the Butter: Cut in 1 cup (2 sticks) of cold, unsalted butter into small cubes. Using a pastry blender or your fingertips, work the butter into the flour mixture until it resembles coarse crumbs. The butter needs to stay cold for a flaky crust, so work quickly! Alternatively, you can pulse the dry ingredients and the cubed butter in a food processor until it resembles coarse crumbs. Don’t over-process!
5. Incorporate Ice Water: Gradually add 6-8 tablespoons of ice water, one tablespoon at a time, mixing until the dough just comes together. Be careful not to overwork the dough, or the crust will be tough. The dough should be moist enough to hold together when gently squeezed, but not sticky. If it is, add just a tiny bit more flour.
6. Divide the Dough: Divide the dough in half. Flatten each half into a disc. Wrap one disc in plastic wrap and place it in the freezer for 30 minutes. This will be the top crust, and freezing it makes it easier to grate.
7. Roll Out the Bottom Crust: On a lightly floured surface, roll out the remaining disc of dough into a rectangle that’s slightly larger than your 9x13 inch baking pan. I sometimes use parchment paper for this step, because it keeps the dough from sticking to the surface. Makes for easy clean up later!
8. Transfer to Pan: Gently transfer the rolled-out dough to the baking pan. Press it into the bottom and up the sides of the pan. Trim any excess dough.
9. Pre-Bake the Crust: Prick the bottom of the crust with a fork. This prevents it from puffing up during baking. Bake the crust in the preheated oven for 15 minutes, or until lightly golden. Remove from the oven and let it cool slightly. You can use baking weights here, too.
10. Prepare the Rhubarb Filling: In a large bowl, combine the chopped rhubarb, 3/4 cup maple syrup, 1/4 cup all-purpose flour, 1 teaspoon vanilla extract, and 1/4 teaspoon ground cinnamon. Gently toss until the rhubarb is evenly coated. This mixture makes the rhubarb both sweeter and thicker.
11. Assemble the Bars: Pour the rhubarb filling evenly over the pre-baked crust.
12. Grate the Top Crust: Remove the frozen disc of dough from the freezer. Using a box grater, grate the frozen dough evenly over the rhubarb filling. Try to do this quickly so the dough doesn't get too warm. Alternatively, you can roll out the top crust and cut into strips, arranging them in a lattice pattern over the filling.
13. Bake the Bars: Bake in the preheated oven for 35-40 minutes, or until the top crust is golden brown and the filling is bubbly. You can tent the bars with foil if the top is browning too quickly.
14. Cool Completely: Let the bars cool completely in the pan before cutting into squares. This allows the filling to set and makes the bars easier to handle. Trust me, it's worth the wait!
15. Serve and Enjoy: Cut into bars and serve. These are great on their own, but even better with a scoop of vanilla ice cream or a dollop of whipped cream.