📖 Instructions

1. Preheat your oven to 375°F (190°C). Grease and lightly flour a 9x13 inch baking pan. For extra insurance against sticking, line the pan with parchment paper, leaving an overhang on the sides.
2. In a large mixing bowl, whisk together the flour, rolled oats, brown sugar, berbere spice, baking powder, and salt. Make sure that berbere spice is evenly distributed, this part is *important*.
3. Add the cold, cubed butter to the dry ingredients. Using a food processor or a pastry cutter, cut the butter into the flour mixture until it resembles coarse crumbs. This will take a few minutes; don’t rush it!
4. In a separate small bowl, whisk together the egg and vanilla extract. Pour this mixture over the crumb mixture and stir until just combined. The dough should be slightly crumbly but hold together when pressed.
5. Press about two-thirds of the crumb mixture into the prepared baking pan, creating an even layer for the crust. Really press it down firmly—I find the bottom of a measuring cup helpful for this step.
6. In a medium mixing bowl, combine the diced rhubarb, sugar, flour, and lemon juice. Toss gently to coat the rhubarb evenly. I personally love adding a pinch of salt here too, its my little secret.
7. Pour the rhubarb mixture over the prepared crust, spreading it evenly across the surface. The rhubarb should be nestled snugly against the crust.
8. Sprinkle the remaining crumb mixture evenly over the rhubarb filling. Don’t worry if there are some gaps—it’ll all bake together beautifully.
9. Bake for 35-40 minutes, or until the crust is golden brown and the filling is bubbly. A toothpick inserted into the center should come out with moist crumbs, not wet batter.
10. Let the bars cool completely in the pan before cutting into squares. This is *crucial*, or they’ll be a mess. Trust me, I’ve learned the hard way! Use the parchment paper overhang to lift the bars out of the pan for easier cutting.
11. Once completely cool, dust the bars with powdered sugar (optional) and cut into squares. Serve and enjoy! These are best enjoyed fresh, but they keep well too.