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2 easiest blueberry crumble bars stacked on each others

The Easiest Blueberry Crumble Bars

These easiest blueberry crumble bars are simply the best. They are buttery, sweet, and loaded with juicy, sour blueberries.
5 from 3 votes
Prep Time: 15 minutes
Cook Time: 35 minutes
1 hour
Total Time: 1 hour 50 minutes
Servings: 9 bars
Calories per serving: 376kcal
Author: Tu

Equipment

Ingredients 

For the crust

  • 2 c AP flour 7.5 oz
  • ½ c old-fashioned rolled oate 1.8 oz
  • ⅓ c brown sugar 1.8 oz
  • ½ tsp Kosher salt 0.1 oz
  • 2 sticks unsalted butter 8 oz, room temperature
  • ¼ tsp baking soda

For filling

  • 2 c blueberries frozen, well drained
  • ¼ c brown sugar 1.5 oz
  • 1 tbsp corn starch 0.4 oz
  • ¼ tsp cinnamon powder
  • 2 tbsp lime juice 1 oz, fresh squeezed

Instructions

  • Pre heat oven to 350 F

For the crust

  • In a large mixing bowl, mix flour, oats, brown sugars, baking soda, and salt.
  • Then add butter to the mixture and use your hand to crumble them together.
  • Press half the flour mixture into the bottom of a baking pan to make a 0.5-inch crust.
  • Pre-bake the crust at 350F for 10 minutes (this step is optional if you want a crunchier bottom crust).

For the filling

  • Drain frozen blueberries in a colander then put them into a medium mixing bowl with lime juice, and stir to combine.
  • Add brown sugar, corn starch, and cinnamon powder to the blueberries mixture. Stir gently with a spatula to evenly combine.

Assemble

  • If you pre-bake the crust, remove the pan from the oven. Let it cool down for 5 minutes.
  • Spread the blueberry filling over the crust and sprinkle the remaining crust mixture evenly over the top.
  • Bake for 30 to 35 minutes, until the berries filling, starts bubbling and the crumbly top turns light golden brown.
  • Let the pan cool down at room temperature for an hour. Slice into nine even bars and serve.

Notes

  1. To soften unsalted butter at room temperature. Like almost other baking recipes that require butter, softened butter is easier to handle and incorporate with other ingredients.
  2. To let the blueberries dry as much as possible. Pat dry (for fresh blueberries) or drain well (for frozen berries) before adding them to the filling to prevent soggy and watery texture.
  3. To use freshly squeezed lime juice. Although it is a small amount, fresh lime juice is always better and doesn't have that bitterness after taste like boxed lime juice.
  4. To let the whole pan cool down almost completely. Slicing warm will have a watery/soupy bars as a result. Not to mention the crumble crust will also be fallen apart easily. Cool for at least 1 hour at room temperature to let the filling set before slicing.
  5. To NOT use your hands when incorporating the butter into the flour mixture. Because your hands' temperature can melt the butter, making a big mess. Use a fork instead.

Nutrition

Calories: 376kcalCarbohydrates: 44gProtein: 4gFat: 21gSaturated Fat: 13gPolyunsaturated Fat: 1gMonounsaturated Fat: 5gTrans Fat: 1gCholesterol: 54mgSodium: 168mgPotassium: 101mgFiber: 2gSugar: 17gVitamin A: 647IUVitamin C: 4mgCalcium: 27mgIron: 2mg