Strawberry Rhubarb Bars
Make Strawberry Rhubarb Bars: buttery oat crumble with jammy strawberry-rhubarb filling, a perfect summer bake.
Ingredients
- 2 cups (192g) rolled or old fashioned oats
- 2 cups (240g) All purpose flour, spooned and leveled
- 1 cup (224g) Lightly packed brown sugar
- 1 teaspoon (5g) Ground cinnamon
- ½ teaspoon Salt
- ¼ teaspoon Baking soda
- 1 cup (113g) Salted butter, at room temperature, cut into ½” pieces
- 1 teaspoon (5ml) Pure vanilla extract
- 3 cups Fresh strawberries, hulled and diced
- 3 cups Fresh rhubarb, diced
- 2 tablespoons (30ml) Fresh lemon juice
- ¼ cup (24g) Cornstarch
- ¾ cup (143g) Granulated sugar
Instructions
Step 1: Preheat and Prepare the Pan
Preheat the oven to 350°F and line a 9×13” rectangular pan with parchment so the paper hangs slightly over the long sides; lightly grease the paper with butter or nonstick spray. Doing this first makes lifting the chilled bars effortless later — set the pan aside on the white quartzite surface while you work on the crumble.
Step 2: Make the Oatty Crumble Base
In a large matte grey ceramic bowl combine rolled oats, all-purpose flour, light brown sugar, ground cinnamon, salt, and baking soda until evenly mixed and sandy in texture. Add room-temperature salted butter cut into ½" pieces and a splash of pure vanilla, then use a sturdy wooden spatula or your fingertips to cut and press the butter into the dry mix until it resembles a rough, sticky cookie-dough — coarse oat clusters, some pebbly crumbs, and larger chunk pockets should remain for crunch.
Step 3: Reserve, Press and Par-bake the Bottom Crust
Scoop off roughly one-third (about 2 scant cups) of the crumble mixture and set it aside in a small bowl. Firmly press the remaining crumble into the bottom of the prepared rectangular pan so the layer is even and neatly sealed to the edges; it should be compacted but still show oat texture. Bake this bottom crust for 10–12 minutes until it’s just starting to pale-golden at the edges.
Step 4: Macerate, Thicken, Assemble and Top
While the crust is baking, toss diced fresh strawberries and diced rhubarb with three tablespoons of the granulated sugar and let sit 5–10 minutes until juices exude; drain off the loose liquid. Return the fruit to the bowl and sprinkle in cornstarch, the remaining sugar, and fresh lemon juice, then gently fold so every piece is evenly coated in a glossy, slightly grainy fruit-sugar slurry. Spread this ruby-pink filling evenly over the par-baked crust, scatter the reserved oat crumble over the top leaving some gaps between chunks, and press the topping lightly into the fruit so pieces adhere and a textured, uneven golden crown forms.
Step 5: Bake Until Bubbling and Golden
Slide the assembled pan back into the oven and bake 45–50 minutes, watching for the filling to deepen into a thickened, slightly glossy jam-like gel and for the crumble to develop an even golden-brown hue with toasted oat edges. Remove from the oven and cool to room temperature on the quartzite surface so the filling sets without running.
Step 6: Chill, Slice and Serve
Refrigerate the cooled slab for at least 1 hour until completely chilled, then lift the bars from the pan using the parchment overhang and cut into neat squares. Arrange a tidy stack of strawberry–rhubarb bars on a simple white plate, garnish with fresh strawberries and a few chopped rhubarb pieces, and serve with a scoop of vanilla ice cream or a dollop of whipped cream.
Notes
- Chill fully before cutting to ensure clean slices.
- Drain macerated fruit well to avoid a runny filling.
- Use old-fashioned oats for better texture; quick oats will make a denser topping.