Ingredients
- All-purpose flour
- Rolled oats (old-fashioned)
- Granulated sugar
- Light brown sugar
- Baking powder
- Ground cinnamon
- Salt
- Unsalted butter
- Fresh rhubarb stalks
- Cornstarch
- Lemon juice
- Vanilla extract
Instructions
- Preheat your oven to 375°F (190°C). Grease and flour a 9×13 inch baking pan, or line with parchment paper, leaving an overhang on the sides for easy removal.
- Prepare the crumb topping and base: In a large bowl, whisk together the flour, rolled oats, granulated sugar, brown sugar, baking powder, cinnamon, and salt. Cut in the cold butter using a pastry blender, two knives, or your fingertips until the mixture resembles coarse crumbs with some larger pea-sized pieces. Reserve about 1.5 cups of this mixture for the topping.
- Press the remaining crumb mixture evenly into the bottom of the prepared baking pan. Bake this base for 10-12 minutes, or until lightly golden. While the base is baking, prepare the rhubarb filling.
- Prepare the rhubarb filling: In a medium bowl, combine the chopped rhubarb, granulated sugar, cornstarch, and lemon juice. Stir gently to coat the rhubarb evenly. The cornstarch will help thicken the filling as it bakes.
- Once the base is lightly baked, remove the pan from the oven. Evenly spread the rhubarb filling over the warm crust. Drizzle the vanilla extract over the rhubarb layer.
- Sprinkle the reserved crumb topping evenly over the rhubarb filling. Return the pan to the oven and bake for an additional 30-35 minutes, or until the topping is golden brown and the rhubarb filling is bubbly and tender when poked with a knife.
- Remove the pan from the oven and let the bars cool completely on a wire rack before cutting. This is crucial for clean cuts and for the filling to set properly, typically 2-3 hours. Once cooled, lift the bars out of the pan using the parchment paper overhang and cut into squares.
- Serve and enjoy! These bars are delicious on their own, or with a dollop of whipped cream or a scoop of vanilla bean ice cream.
Notes
For best results, use fresh, firm rhubarb. If using frozen rhubarb, do not thaw; toss it directly with the sugar and cornstarch, and bake a few minutes longer. Store leftover bars in an airtight container at room temperature for up to 3 days, or refrigerate for up to a week. They also freeze beautifully for up to 3 months. For an extra hint of warmth, add a pinch of nutmeg or cardamom to the crumb mixture. A half cup of chopped walnuts or pecans can also be added to the crumb topping for extra crunch.
- Prep Time: 20 minutes
- Cook Time: 40 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 bar (1/16th of recipe)
- Calories: 280
- Sugar: 25g
- Sodium: 180mg
- Fat: 14g
- Saturated Fat: 9g
- Unsaturated Fat: 4g
- Trans Fat: 0g
- Carbohydrates: 38g
- Fiber: 2g
- Protein: 3g
- Cholesterol: 40mg