Rhubarb Oat Bars Crumble

These Rhubarb Oat Bars are my go-to treat whenever rhubarb makes its first appearance at the market. The crumbly oat crust sandwiched with a jammy rhubarb filling is just like a cozy summer crumble, only easier to share and perfect for picnics or family gatherings.

I grew up picking rhubarb in my grandma’s garden and these bars always take me right back to those simple afternoons outside. The sweet tang tucked between oat layers never fails to get rave reviews from friends.

Ingredients

• Chopped rhubarb: provides a tart syrupy filling always choose firm crisp stalks with bright color
• Sugar: sweetens the rhubarb and balances the tang
• Lemon juice: brightens the flavor opt for freshly squeezed if possible
• Water: helps the filling break down
• All purpose flour: gives structure to the crust use a good quality unbleached flour
• Quick oats: create the classic chewy crumbly texture
• Melted butter: holds everything together use real butter for the best flavor
• Salt: brings out all the other flavors just a little goes a long way
• Cinnamon and sugar for topping: adds a warmly spiced crunch try using ground cinnamon with a sweet aroma

Step-by-Step Instructions

Get Ready:

Preheat your oven to 350 degrees Fahrenheit and line a nine inch square baking pan with parchment paper making sure it goes up the sides for easy removal later

Make the Rhubarb Filling:

In a medium saucepan combine chopped rhubarb sugar water and a generous squeeze of lemon juice. Simmer on low medium heat for about ten minutes stirring occasionally. You want the rhubarb to turn soft and jammy but keep some chunks for texture. Set the mixture aside to cool slightly

Mix the Oat Crust:

In a large bowl thoroughly combine flour quick oats sugar and salt. Pour in the melted butter and stir with a spoon or your hands until the mixture becomes evenly moist and crumbly. Scoop out half a cup of this oat mixture and set it aside for topping

Press the Crust:

Pour the remaining oat mixture into your lined pan and press it down very firmly and evenly to cover the entire base This is key for a sturdy bar

Layer the Filling:

Evenly spread the cooked rhubarb mixture over the pressed oat crust spreading right to the edges

Add Topping and Bake:

Sprinkle the reserved oat mixture on top of the rhubarb filling scatter it either evenly or in rustic clusters to your liking. Dust the top with cinnamon and sugar for extra flavor and crunch. Bake in the center of your oven for about one hour until the top is golden brown and you see the rhubarb bubbling around the edges

Cool and Slice:

Remove the pan from the oven and cool completely for at least two hours before slicing into bars This helps the filling set and gives clean slices

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I am always amazed at how the oat topping crisps up just right every time my favorite bites are always the corner pieces that get extra golden

Storage Tips

Let your bars cool completely before moving them to an airtight container You can keep them at room temperature for a day but for longer storage refrigerate them They taste great cold or at room temperature For freezing wrap well and freeze in a single layer They thaw nicely in the fridge

Ingredient Substitutions

Fresh rhubarb works best but frozen rhubarb is fine just thaw and drain before using If you run out of oats you can try half oats and half chopped nuts for extra crunch Gluten free flour blends can successfully swap for regular flour if needed For a vegan option use melted coconut oil instead of butter

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Serving Suggestions

Serve these bars as a dessert with a scoop of vanilla ice cream at a summer barbecue or pack them for a picnic in the park They also pair wonderfully with an afternoon cup of tea For extra flair dust with a little powdered sugar just before serving

Cultural Context

Rhubarb has been a classic dessert ingredient in Northern climates where its tart flavor is adored in crumbles and pies Turning it into a bar makes for easier sharing and introduces kids and new eaters to this old fashioned favorite

Recipe FAQs

→ How do I ensure my rhubarb filling is not too runny?

Simmer rhubarb gently until softened but still chunky. Letting it cool slightly thickens the mixture for a perfect layered bar.

→ Can I use rolled oats instead of quick oats?

Quick oats create a finer texture. Rolled oats can work, but expect a chewier, more rustic feel in the crust and topping.

→ Why is it important to cool the bars before cutting?

Cooling allows the rhubarb filling to set and the oat base to firm up, making neat slices and cleaner serving easier.

→ How can I enhance the flavor of the oat topping?

A cinnamon-sugar sprinkle adds warmth and extra sweetness to complement the tart rhubarb layer.

→ Can these bars be made ahead and stored?

Yes, store the bars in an airtight container at room temperature for two days, or refrigerate for longer freshness.