Strawberry Rhubarb Crisp With Buttery Oat Topping

Sweet strawberries and tart rhubarb bake down into a jammy filling under a crisp oat topping that turns golden and buttery in the oven. This strawberry rhubarb crisp is the kind of easy summer dessert that works for weeknight baking, potlucks, or using up fresh rhubarb while it’s in season.

Ingredients

For the Fruit Filling

• 4 cups chopped rhubarb
• 3 cups sliced strawberries
• 1/2 cup granulated sugar
• 1/4 cup light brown sugar
• 3 tablespoons cornstarch
• 1 teaspoon vanilla extract
• 1 tablespoon lemon juice
• Pinch of salt

For the Oat Crisp Topping

• 1 cup old-fashioned oats
• 3/4 cup all-purpose flour
• 3/4 cup light brown sugar
• 1 teaspoon cinnamon
• 1/2 teaspoon salt
• 1/2 cup cold unsalted butter, cubed

Fresh rhubarb works best here because it keeps a little texture after baking. If using frozen strawberries, thaw and drain them first so the filling does not turn watery.

How To Make It

1. Preheat the oven to 375°F and lightly grease a 9-inch baking dish. In a large bowl, toss the rhubarb, strawberries, sugars, cornstarch, vanilla, lemon juice, and salt until the fruit looks evenly coated and glossy.

2. Spread the fruit mixture into the baking dish. The filling may seem slightly dry at first, but the strawberries and rhubarb release plenty of juice as they bake.

3. In another bowl, mix the oats, flour, brown sugar, cinnamon, and salt. Cut in the cold butter with a pastry cutter or your fingertips until the mixture forms chunky crumbs with pea-sized bits of butter throughout.

4. Sprinkle the oat topping evenly over the fruit. Leave some larger clumps intact because those pieces bake into the crispiest topping.

5. Bake for 35 to 45 minutes, until the fruit filling is bubbling hard around the edges and the topping turns deep golden brown. One thing to watch for is pale topping in the center — if needed, bake an extra 5 minutes for more color and crunch.

6. Let the strawberry rhubarb crisp cool for at least 15 minutes before serving. The filling thickens as it cools, making it easier to scoop.

Why This Works

Strawberries soften the sharp tartness of rhubarb without hiding its flavor, which is why this combination shows up in so many classic summer rhubarb desserts. A small amount of cornstarch thickens the fruit juices so the filling stays spoonable instead of soupy.

The oat topping uses cold butter rather than melted butter, which helps create crisp clusters instead of a sandy crumble. Many home cooks find that old-fashioned oats give the topping a better texture than quick oats.

For more rhubarb baking tips, this guide from Serious Eats explains how rhubarb behaves in crisps and crumbles.

Tips

• If the fruit filling seems too loose after baking, let the crisp rest another 10 to 15 minutes before serving.
• A common tip is to place the baking dish on a sheet pan to catch any bubbling juices.
• If your topping browns too quickly, loosely tent the dish with foil during the last 10 minutes of baking.
• For extra texture, add 1/2 cup chopped pecans or walnuts to the oat topping.
• If you enjoy fruit-forward desserts, this peach cobbler recipe pairs well with the same style of buttery topping and summer fruit flavor.

Serving Ideas

Serve strawberry rhubarb crisp warm with vanilla ice cream or lightly sweetened whipped cream. The cold cream balances the tart fruit filling especially well.

It also works well as a brunch-style summer rhubarb dessert with plain Greek yogurt spooned over the top. For another fruit dessert with a soft baked filling, Taste Better From Scratch has a version that uses citrus for extra brightness.

FAQ

Can I make strawberry rhubarb crisp ahead of time?

Yes. You can assemble the entire dish a few hours ahead and refrigerate it before baking. If baking straight from the fridge, add about 5 extra minutes to the baking time so the center heats through completely.

Can I freeze rhubarb crisp?

The baked crisp freezes well for up to 2 months. Cool it fully first, then wrap tightly. Reheat in a 350°F oven until the topping becomes crisp again and the filling is hot.

Why is my crisp topping not crunchy?

This usually happens if the butter was too soft or the crisp was underbaked. The topping should look deeply golden and dry on top before coming out of the oven.

Can I use frozen rhubarb?

Yes, but thaw and drain it first. Frozen rhubarb releases extra liquid, so skipping this step can make the filling watery.

What can I use instead of cornstarch?

All-purpose flour or tapioca starch both work as thickeners in this rhubarb crisp recipe. Tapioca starch gives the filling a slightly glossier finish.