Rhubarb Lemon Crumble Bars
These bars are everything I want from a spring dessert – buttery, bright, tart, cozy, and just messy enough in the best way possible. The soft lemony rhubarb layer melts into a buttery shortbread base, then gets topped with a golden oat crumble that gives the perfect little crunch. They taste like something between a crumble, a pie bar, and a buttery lemon square.
I love making these when rhubarb season hits because they feel rustic and nostalgic without needing to be perfect. The tart rhubarb with the fresh lemon keeps everything tasting light and fresh, while the shortbread and crumble make them feel rich and comforting. Perfect with coffee, as a snack straight from the fridge, or warmed up with vanilla ice cream.
Rhubarb Lemon Crumble Bars
Ingredients
Shortbread Crust
- 1 cup butter room temperature
- 2/3 cup sugar
- Zest of 1 lemon
- 1 tsp vanilla bean paste
- 2 heaping cups flour
- About 2 tbsp water or enough to create a crumbly dough
Rhubarb Lemon Filling
- 8 rhubarb stalks chopped
- 1/2 cup white sugar
- Zest of 1 lemon
- Juice of 1 lemon
- 1 heaping tbsp cornstarch
Oat Crumble
- 1 cup oats
- 1/2 cup sliced almonds optional
- 3/4 cup brown sugar
- 1/4 cup flour
- 1 tsp cinnamon optional
- 1/2 cup butter melted
Instructions
- Preheat oven to 350°F and line a large baking pan with parchment paper.
- For the shortbread crust, rub the lemon zest into the sugar with your fingers until fragrant. Cream the lemon sugar together with the butter until smooth and fluffy. Mix in the vanilla bean, flour, and water until a crumbly dough forms that sticks together when pressed. Press evenly into the prepared pan.
- For the rhubarb filling, add the chopped rhubarb, sugar, lemon zest, and lemon juice to a saucepan over low heat. Cook until the rhubarb softens slightly but still holds its shape. Stir in the cornstarch and cook until the mixture thickens.
- Spread the rhubarb mixture evenly over the shortbread crust.
- For the crumble topping, stir together the oats, sliced almonds, brown sugar, flour, cinnamon, and melted butter until combined and crumbly. Sprinkle evenly over the rhubarb layer. If the mixture is too dry, add more butter. If it's too wet, add more flour.
- Bake for about 40 minutes, or until golden and bubbling around the edges. Start checking around the 30 minute mark depending on your oven. Let cool completely before slicing into bars.
Used in this recipe
