Strawberry Oatmeal Crumble Bars

This strawberry oatmeal crumble bar recipe has become my summer go-to dessert whenever fresh berries are in season. The combination of buttery oat crumble and sweet-tart strawberry filling creates the perfect balance of flavors and textures that keeps everyone coming back for seconds.

I first made these bars for a backyard barbecue when I needed something quick that could sit out in the summer heat. They disappeared faster than any other dessert, and now my daughter requests them for every special occasion.

Ingredients

• Unsalted butter: Gives these bars their rich, buttery foundation while allowing you to control the salt content
• All-purpose flour: Provides structure without making the bars too dense
• Old-fashioned oats: Add wonderful texture and a nutty flavor that complements the strawberries
• Granulated sugar: Balances the tartness of the berries while helping the filling achieve that perfect jammy consistency
• Light brown sugar: Brings a subtle caramel note to the crumble mixture
• Fresh strawberries: The star here. Look for bright red berries with a sweet fragrance
• Lemon juice: Brightens the strawberry filling and helps preserve the vibrant color
• Cornstarch: Thickens the filling so your bars hold together when sliced

Step-by-Step Instructions

Prepare the pan:

Line an 8-inch square pan with aluminum foil and spray with cooking spray. This might seem like an extra step, but trust me, it makes cleanup infinitely easier and ensures your bars come out intact.

Make the crumble mixture:

Melt butter in a large bowl until completely liquid but not too hot. Add flour, oats, both sugars, and salt, then stir until combined. The mixture will look sandy with some larger clumps forming. Take your time here to ensure everything is evenly incorporated.

Form the crust:

Reserve about one heaping cup of the mixture for the topping. Press the remaining mixture firmly into your prepared pan. Use the back of a measuring cup to really compact it down, creating a solid foundation that will support your filling.

Prepare the strawberry filling:

Coarsely chop strawberries so they break down nicely while baking but still maintain some texture. Toss with sugar, lemon juice, and cornstarch until evenly coated. The sugar might not fully dissolve at this point, which is perfectly fine.

Assemble and bake:

Pour the strawberry mixture over the crust, spreading it evenly to all corners. Squeeze the reserved crumble mixture in your palm to create larger clumps before sprinkling over the strawberries. Bake until the edges set and the filling bubbles, about 50 minutes.

Cooling period:

Allow the bars to cool completely before cutting. This step is absolutely crucial as the filling needs time to set properly. I know it's tempting to cut in while still warm, but patience yields perfect squares.

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The secret to these bars is using old-fashioned rolled oats rather than quick oats. I learned this lesson the hard way after a batch turned out too dry and crumbly. The larger oats provide that perfect chewy texture while still giving the bars enough structure to hold together.

Storage Solutions

These crumble bars maintain their quality remarkably well over time. For room temperature storage, place them in an airtight container with parchment between layers to prevent sticking. They'll stay fresh for about a week. For longer storage, refrigerate them for up to 10 days. The refrigeration actually improves the texture slightly, making the filling more firm and easier to eat without making a mess.

Perfect Pairings

Serve these strawberry crumble bars slightly warm with a scoop of vanilla ice cream for an elevated dessert experience. The contrast between the warm, fruity bars and cold, creamy ice cream creates a wonderful temperature and texture play. For brunch, they pair beautifully with coffee or tea. You can also dress them up by adding a drizzle of white chocolate or a dollop of freshly whipped cream for special occasions.

Berry Variations

While strawberries shine in this recipe, you can easily substitute other berries or create delightful combinations. Blueberries work wonderfully on their own, creating a deeper, more jammy filling. A mixed berry version with raspberries, blackberries, and blueberries offers complex flavor notes. When using juicier berries like blackberries, consider adding an extra teaspoon of cornstarch to ensure your filling sets properly.

Frequently Asked Questions

→ Can I use frozen strawberries?

Yes, frozen strawberries can be used. However, they may release more liquid during baking. Consider adding an extra teaspoon of cornstarch to the strawberry layer to help thicken the filling.

→ What type of oats should I use?

Use old-fashioned oats for the best texture. Avoid quick-cook or instant oats, as they can make the mixture too dry.

→ How do I store the bars?

Store the bars airtight at room temperature for up to a week, in the fridge for 10 days, or freeze them for up to 6 months.

→ Why is the crumble topping not forming clumps?

Squeeze the crumble mixture firmly in your palm before sprinkling it over the strawberries to encourage larger clumps to form.

→ Can I substitute the strawberries with other fruits?

Yes, you can substitute strawberries with other fruits like blueberries, raspberries, or peaches for a different flavor.

→ What is the best way to slice the bars cleanly?

Allow the bars to cool completely for at least an hour before slicing to avoid them falling apart or becoming messy.