featured 18019

Strawberry Rhubarb Dessert Bars with Oat Crumble

Strawberry rhubarb bars have a delicious oatmeal base, a strawberry rhubarb middle that’s both sweet and tart, and a cinnamon oatmeal crumble topping. The perfect summer dessert—excellent with a midmorning coffee or a scoop of ice cream. Stack of three strawberry rhubarb bars

These bars take everything you love about a strawberry rhubarb crisp and make it portable and easy to serve. The base is a thick, chewy oatmeal layer, the filling balances sweet strawberries with slightly tart rhubarb, and the topping is a crunchy cinnamon oat crumble. They’re dessert-worthy but also delicious for breakfast when you want something indulgent.

Making the Bars

Strawberry Rhubarb Filling

There’s no need to cook the fruit beforehand. Toss sliced strawberries, chopped rhubarb, sugar, cornstarch, and a splash of fresh lemon or orange juice until evenly coated. The cornstarch thickens the filling as it bakes, while the citrus brightens the fruit flavor. During baking the fruit softens and forms a jammy layer.

Bowl of ingredients for strawberry rhubarb filling, and bowl of ingredients mixed together

Oatmeal Base & Topping

The oatmeal mixture serves as both the base and the crumble topping with one simple method:

  1. Whisk together flour, brown and white sugars, cinnamon, salt, and baking powder.
  2. Stir in melted butter until the mixture is slightly crumbly and evenly moistened.
  3. Fold in rolled oats until combined.

The mixture comes together quickly by hand—no electric mixer required. Bowl of ingredients for oatmeal crumble & bowl of oatmeal crumble mixture.

Assembling the Bars

Press a little over half of the oatmeal mixture into the bottom of a prepared 9×13-inch baking pan to form the base. Spread the fruit filling evenly over the base, leaving excess juices in the bowl if there is a lot. Crumble the remaining oat mixture over the fruit—pinch it into larger clumps or sprinkle finer crumbs depending on the texture you prefer.

Bake at 350°F (180°C) for about 40–50 minutes, or until the top is golden and fruit juices are gently bubbling. Let the bars cool completely so the filling sets before slicing. Pan of strawberry rhubarb crumble bars

Baking Tips & Tricks

  • Fresh fruit is preferred. Using frozen fruit will lengthen bake time and can release extra liquid.
  • The oatmeal mixture should feel slightly dry and crumbly before baking—that’s normal.
  • Cool completely before slicing so the filling firms up and the bars cut cleanly.

Stack of 3 strawberry rhubarb oatmeal bars.

Recipe

Ingredients

Strawberry Rhubarb Layer

  • 2 cups sliced strawberries (measure after removing cores & slicing)
  • 2 cups chopped rhubarb (about 1/5–1/4 inch slices)
  • 1/2 cup granulated sugar (100 g)
  • 3 tablespoons cornstarch (24 g)
  • 2 tablespoons lemon or orange juice, freshly squeezed

Oatmeal Crumble Base & Topping

  • 2 cups all-purpose flour (250 g)
  • 1 cup brown sugar (210 g), light or dark
  • 1/2 cup white sugar (100 g)
  • 1 teaspoon cinnamon
  • 1/2 teaspoon salt
  • 1 3/4 cup rolled oats (preferably large)
  • 1 cup unsalted butter (226 g), melted

Equipment

  • 9×13 inch (23 x 33 cm) baking pan

Instructions

  1. Preheat oven to 350°F (180°C). Lightly grease a 9×13 pan or line it with parchment, leaving an overhang for easy removal.
  2. In a large bowl, toss strawberries, rhubarb, sugar, cornstarch, and lemon (or orange) juice until evenly coated; set aside.
  3. In a separate large bowl, whisk flour, brown sugar, white sugar, cinnamon, salt, and oats until smooth and even. Stir in melted butter until the mixture is slightly crumbly and moistened.
  4. Press a little over half of the oat mixture into the bottom of the prepared pan to form an even base.
  5. Spoon the fruit mixture over the base, leaving excess juices behind if there’s a lot.
  6. Crumble the remaining oat mixture over the fruit layer.
  7. Bake for 40–50 minutes, until the top is golden and fruit juices are gently bubbling through.
  8. Cool completely before slicing. If lined with parchment, lift the bars from the pan using the paper overhang for easier cutting.

Notes

  1. Pan sizes: The recipe can be halved for an 8×8 inch (20×20 cm) pan; bake time will be closer to 35–45 minutes.
  2. Frozen fruit: If using frozen, add at least 5–10 minutes to the bake time and consider tenting with foil to prevent overbrowning. Frozen fruit can release extra liquid, which may affect the base.
  3. Storage: Store in an airtight container at room temperature up to 3 days, or refrigerate up to 5 days. Bars freeze well; thaw in the fridge.
  4. Nutrition: Provided values are estimates per bar if the pan is cut into 15 pieces.

Nutrition (approx. per bar)

Calories: 328 kcal; Carbohydrates: 51 g; Protein: 3 g; Fat: 13 g; Sugar: 29 g