Blueberry-Streusel Bars with Lemon Cream Filling

Sometimes I feel like I spend way too much time sitting in front of my computer, staring at the screen for hours upon hours each day.  Sure, much of it is productive and necessary – editing photos, writing blog posts, responding to emails, etc but there’s a segment (ok, a big segment) that’s mostly just for fun.  Twitter falls squarely in that category.  On more than one occasion I’ve thought about stepping away since it can be such a huge distraction, but I always find a reason to stick around.  A big one: deals!  Twitter is one of the best ways I learn about sales I probably would otherwise have missed.  For example, a huge one-day sale on blueberries at Whole Foods last Friday.  A sale so nice that it prompted me to email Shane and ask him to stop at the location near his office on the way home and grab a bunch for me.  I’d had my eye on the recipe for these blueberry-streusel bars for a few weeks, and my new stash of blueberries afforded me an opportunity to make them just in time to share at our Father’s Day cookout this weekend.

Let me just cut to the chase – I absolutely loved everything about these bars.  Their base is a chewy oat-studded crust, which is topped with fresh blueberries that soften and become incredibly juicy during the baking process.  Atop the blueberries is a super simple, smooth lemon cream filling made using lemon juice, zest and condensed milk.  It sets up perfectly in the oven and really adds both texture and flavor to the bars.  The lemon isn’t overpowering; I think it adds just enough tartness to balance the sweetness of the other elements.  The final layer is a streusel made using reserved crumbs from the crust, and like all good streusels, it’s completely irresistible.

One of my biggest problems with bars is that they’re sometimes difficult to cut neatly, but I didn’t run into that issue here.  If you want to ensure a super clean cut, just refrigerate the bars briefly first.  Be sure to use room temperature berries as the recipe suggests, or your result may not be as successful.  I usually stick my berries in a strainer and wash them, then spread them in a single layer on a towel set in a rimmed baking sheet.  Not only will they dry quickly, but it makes it easier to pick out any damaged berries or random stems.  I always wash a few more than I need to allow for snacking – a full tray of berries is too hard to walk by without grabbing a handful.  I can’t wait to make this recipe again after I pick my own berries later this summer

Blueberry-Streusel Bars with Lemon Cream Filling
from Fine Cooking

3 cups (13-1/2 oz) all-purpose flour
1 1/2 cups rolled oats (not quick oats)
1 1/3 cups packed light brown sugar
1 teaspoon salt
1 teaspoon baking powder
1 cup (2 sticks) unsalted butter, at room temperature
1 large egg, separated
14 oz can sweetened condensed milk
1/2 cup fresh lemon juice
2 teaspoons lemon zest
2 1/2 cups (about 13 oz) room-temperature blueberries

Preheat oven to 350 F.  Line a 13×9 metal baking pan with foil, leaving a slight overhang on both sides to lift the bars out.  Spray the pan/foil with cooking spray.

Whisk the flour, oats, brown sugar, salt and baking powder together in a large bowl.  Use a pastry blender (or your fingers) to cut the butter into the dry ingredients completely.  (In other words, until the pieces of butter aren’t visible anymore.)  Set aside and reserve 2 cups of these crumbs for the topping. Beat the egg white with a fork until broken up and foamy.  Add it to the crumbs and mix to incorporate.  Transfer the mixture to the prepared pan and press to form an even layer of crust.  Bake for about 10-12 minutes, or until the top starts to look dry.

Meanwhile, whisk the condensed milk, lemon juice, lemon zest, and egg yolk together in a medium bowl.  Let stand for 5 minutes; the mixture will begin to thicken slightly.

When the crust has finished baking, transfer the pan to a wire rack and sprinkle the blueberries evenly over the hot crust.  Drop spoonfuls of the lemon mixture over the blueberries then spread the lemon mixture gently to distribute it.  Work carefully so you don’t crush the berries; the lemon layer doesn’t have to cover every bit of the crust.  Bake until the lemon layer begins to form a shiny skin, about 7-8 minutes.

Remove the pan to a wire rack and use your fingers to press the reserved crumb mixture into small clumps and sprinkle them over the lemon layer.  Use all of the crumb mixture to cover the lemon layer completely.  Bake for 25-30 minutes, or until the filling is bubbling at the edges and the streusel topping is golden brown.

Transfer the pan to a wire rack and let the bars cool for about an hour, until just warm.  Remove them from the pan using the foil overhang and let cool completely on the wire rack.  Cut into squares before serving.  The bars should be stored in the refrigerator.