Blueberry Lemon Cream Streusel Bars are a delicious way to use fresh, juicy summer blueberries. These easy-to-make cookie bars deliver a bright lemon cream filling and a crunchy cinnamon streusel topping that’s simply irresistible.
Making these bars reminded me of the playful character Violet Beauregarde from Roald Dahl’s Charlie and the Chocolate Factory—cheeky, bold, and impossible to ignore. These bars are just as memorable: once you try one, it’s hard to stop at just one. Fortunately, they’re easy to share, freeze well, and make a wonderful addition to summer gatherings.
These bars balance tart and sweet flavors—fresh lemon brightens the sweetened condensed milk filling while the juicy blueberries add bursts of summer. The oat-and-flour base bakes into a sturdy, buttery crust, and a generous streusel layer provides a delightful crunch with a hint of cinnamon. The recipe yields a full 9×13 pan and takes less than an hour of active time, plus baking and cooling. They’re ideal for Memorial Day picnics, backyard parties, potlucks, or a simple afternoon treat with tea or coffee.
Storage and make-ahead tips: these bars freeze very well. Once cooled, wrap squares individually or place several in a sealed freezer bag or container. Thaw at room temperature or gently in the refrigerator before serving. At room temperature they can sit out for a short time, but for longer storage keep them refrigerated—then bring to room temperature before eating for the best flavor and texture.
Quick blueberry notes: blueberries are considered a nutrient-rich fruit and are high in antioxidants. Picking season generally runs from late June through August. When selecting berries, look for plump, silvery-blue fruit—avoid red or green berries, which are not fully ripe. Blueberries do not continue to ripen significantly after picking, so choose fully colored ones for maximum sweetness and flavor.
Blueberry Lemon Cream Streusel Bars
Pin Recipe
Ingredients
- 1 cup (2 sticks) unsalted butter, melted
- 2 cups all-purpose flour
- 1 1/2 cups old fashioned oats, not quick oats
- 1 cup light brown sugar, packed
- 1/2 cup granulated sugar
- 1 tsp. cinnamon
- 1 tsp. baking powder
- 1/2 tsp. salt
- 1 14-oz. can sweetened condensed milk
- 1/2 cup fresh lemon juice
- 1 1/2 tsp. grated lemon zest
- 1 large egg yolk
- 1 tsp. vanilla
- 3 cups blueberries, washed and dried
Instructions
- Preheat the oven to 350°F (175°C). Position a rack in the center. Line a 9×13-inch pan with foil, leaving an overhang for easy removal, and lightly spray the foil with non-stick cooking spray.
- In a large bowl, combine the flour, oats, brown sugar, granulated sugar, cinnamon, baking powder, and salt. Stir in the melted butter until the mixture becomes crumbly. Reserve 2 cups of this crumb mixture for the streusel topping. Press the remaining mixture evenly into the bottom of the prepared pan to form the crust. Bake the crust for 12 minutes.
- While the crust bakes, whisk together the sweetened condensed milk, fresh lemon juice, lemon zest, egg yolk, and vanilla in a medium bowl until smooth.
- Remove the partially baked crust from the oven and evenly scatter the blueberries over it. Drop spoonfuls of the lemon mixture over the berries and gently spread with the back of a spoon—don’t worry if it’s not perfectly smooth. Bake for 8 minutes.
- Sprinkle the reserved streusel topping over the lemon and blueberry layer, then bake for an additional 30 minutes, until the top is lightly browned and bubbling.
- Allow the bars to cool on a wire rack for about 45 minutes. Use the foil overhang to lift the bars from the pan and let them cool completely on the rack. Peel back the foil and cut into bars. Store at room temperature for a short time, then refrigerate for longer storage.