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For the best Blueberry Crumble Bars, use fresh ingredients. You need: - 2 cups fresh blueberries - 1 tablespoon lemon juice - 1/4 cup granulated sugar (adjust based on blueberry sweetness) - 1 teaspoon cornstarch Fresh blueberries give the bars a juicy and sweet flavor. The lemon juice brightens the taste, while sugar sweetens it. Cornstarch helps thicken the filling. You will also need some common baking staples. Gather these: - 1 1/2 cups all-purpose flour - 1/2 cup rolled oats - 1/2 cup brown sugar, packed - 1/2 teaspoon baking powder - 1/4 teaspoon salt - 1/2 cup unsalted butter, melted - 1 teaspoon vanilla extract Flour and oats create a great crumble. Brown sugar adds depth, while baking powder helps the bars rise. Salt balances the sweetness, and butter brings everything together. You can tweak the recipe to suit your taste. If your blueberries are very sweet, use less granulated sugar. You can also try swapping the brown sugar for coconut sugar for a different flavor. If you want a lighter option, use less butter or a butter substitute. These small changes can help make the bars just right for you. {{ingredient_image_1}} First, preheat your oven to 350°F (175°C). Grease an 8x8-inch baking dish with butter or cooking spray. This step helps the bars come out easily after baking. In a mixing bowl, gently combine the fresh blueberries with 1 tablespoon of lemon juice, 1/4 cup of granulated sugar, and 1 teaspoon of cornstarch. Mix these ingredients carefully to avoid squishing the berries. Let this sit for a few minutes. This time allows the flavors to blend and the cornstarch to thicken. In another bowl, whisk together 1 1/2 cups of all-purpose flour, 1/2 cup of rolled oats, 1/2 cup of brown sugar, 1/2 teaspoon of baking powder, and 1/4 teaspoon of salt. These ingredients form the tasty crumb base and topping. Next, pour in 1/2 cup of melted unsalted butter and 1 teaspoon of vanilla extract. Mix until the dry ingredients get coated and the mixture becomes crumbly. Take about two-thirds of this mixture and press it firmly into the bottom of your greased baking dish. Make sure it's even and covers the entire base. Now, take the blueberry mixture and spoon it evenly over the pressed crumble base. Spread the blueberries gently so they cover the whole area. Finally, sprinkle the remaining crumble mixture over the blueberries. Ensure it's distributed evenly for the best texture. Bake the dish in the preheated oven for 30-35 minutes. You want the top to turn golden brown and the blueberries to bubble. Let the bars cool in the pan for at least 15 minutes before slicing into squares. To get the best crumble, use cold butter. Cut it into small cubes and mix it in. This keeps the mixture crumbly. You want to see small clumps of butter. Don’t over-mix; stop when the mix looks sandy but holds together. The oats add a nice chewiness too. I love serving these bars warm. They taste great with a scoop of vanilla ice cream. Dusting them with powdered sugar adds a sweet touch. You can also enjoy them plain or with fresh berries on top. They are perfect for breakfast or dessert! A common mistake is using soft butter. It makes the crumble too smooth. Always measure your flour correctly; too much can make it dry. Don’t skip the cornstarch in the filling. It helps thicken the blueberries and keeps the bars from being too runny. Lastly, let them cool before slicing; it makes cutting easier! Pro Tips Use Fresh Blueberries: Fresh blueberries will provide the best flavor and texture for your crumble bars. If using frozen, make sure to thaw and drain excess moisture. Adjust Sweetness: Depending on the ripeness of your blueberries, you may need to adjust the sugar content. Taste the mixture before baking to find the perfect balance. Perfect Crumble Texture: For a crumbly topping, ensure your butter is melted but not too hot. Mix until just combined to keep the texture nice and crumbly. Let Cool Before Slicing: Allow the bars to cool for at least 15 minutes before slicing. This helps them set and makes for cleaner cuts. {{image_2}} You can make these blueberry crumble bars gluten-free. Use gluten-free all-purpose flour instead of regular flour. Check the flour blend to ensure it works well in baking. This small change makes the bars safe for gluten-sensitive friends without losing flavor or texture. To make this recipe vegan, swap butter for coconut oil or a vegan butter. You can also use maple syrup or agave syrup instead of granulated sugar. For the egg, use unsweetened applesauce (1/4 cup per egg) if you decide to add it for moisture. These swaps keep the bars tasty while meeting vegan needs. You can add fun flavors to your bars. Mix in chopped nuts like walnuts or pecans for crunch. Add spices like cinnamon or nutmeg to give warmth and depth. A little zest from an orange or lemon brightens the blueberries. These extras can make your bars unique and exciting. To keep your blueberry crumble bars fresh, store them in an airtight container. Use parchment paper to separate layers if you stack them. This helps prevent sticking. Place the container in the fridge for best results. If you want to keep them longer, you can freeze them. In the fridge, these bars last about 3 to 5 days. The blueberries stay juicy, and the crumble remains tasty. If frozen, they can last up to 3 months. Just make sure to wrap them well to avoid freezer burn. To reheat, take a bar and place it on a microwave-safe plate. Heat it for 15 to 20 seconds. This warms the bar and makes the blueberries soft again. You can also bake them in the oven. Set the oven to 350°F (175°C) and warm the bars for about 10 minutes. This makes the crumble nice and crisp again. Enjoy warm for the best flavor! Yes, you can use frozen blueberries. They work well in this recipe. Just add them straight from the freezer. You may want to increase the baking time slightly. The filling might be a bit juicier, but it will still taste great! Adjust the sugar based on the sweetness of your blueberries. If they are tart, add more sugar. If they are sweet, use less. Start with the 1/4 cup sugar and taste the mixture. This way, you make sure the filling is just right. Absolutely! You can double the recipe. Use a larger baking dish, like 9x13 inches. Just keep an eye on the baking time. Larger bars may need a few extra minutes to bake fully. If you need a butter substitute, try coconut oil or vegan butter. Both options work well in this recipe. They will keep the crumble nice and rich. Just melt them the same way you would butter. Yes, these bars freeze well! Once cooled, wrap them in plastic wrap or foil. Store them in an airtight container. They can last up to three months in the freezer. Just thaw them in the fridge before serving. This article covered how to make delicious blueberry crumble bars. You learned about fresh ingredients needed, baking staples, and simple adjustments. I shared step-by-step instructions for baking and tips for the perfect texture. Plus, I offered storage info and answered common FAQs. Blueberry crumble bars are easy and fun to make. Enjoy experimenting with variations to suit your taste. With these tips, your baking will shine. Happy baking!

Blueberry Crumble Bars

Delicious and easy-to-make blueberry crumble bars, perfect for dessert or a sweet snack.
Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 35 minutes
Total Time 50 minutes
Course Dessert
Cuisine American
Servings 16
Calories 150 kcal

Ingredients
  

  • 2 cups fresh blueberries
  • 1 tablespoon lemon juice
  • 0.25 cup granulated sugar
  • 1 teaspoon cornstarch
  • 1.5 cups all-purpose flour
  • 0.5 cup rolled oats
  • 0.5 cup brown sugar, packed
  • 0.5 teaspoon baking powder
  • 0.25 teaspoon salt
  • 0.5 cup unsalted butter, melted
  • 1 teaspoon vanilla extract

Instructions
 

  • Preheat your oven to 350°F (175°C) and grease an 8x8-inch baking dish.
  • In a mixing bowl, gently combine the blueberries, lemon juice, granulated sugar, and cornstarch. Set aside to allow flavors to meld.
  • In another bowl, whisk together the flour, rolled oats, brown sugar, baking powder, and salt.
  • Pour in the melted butter and vanilla extract, then mix until crumbly and the dry ingredients are evenly coated.
  • Press about two-thirds of the crumble mixture into the base of the prepared baking dish, creating an even layer.
  • Spoon the blueberry mixture evenly over the crumble base, spreading it out gently.
  • Sprinkle the remaining crumble mixture over the blueberries, ensuring it's distributed evenly.
  • Bake in the preheated oven for 30-35 minutes, or until the top is golden brown and the blueberries are bubbly.
  • Once baked, allow the bars to cool in the pan for at least 15 minutes before slicing into squares.

Notes

Serve warm or at room temperature, dusted with powdered sugar. Pair with vanilla ice cream for an indulgent treat!
Keyword bars, blueberry, crumble, dessert