Blackberry Bars with Rosemary and Lemon

Ingredients

• cooking spray
• Crumb Topping:
• ½ cup white whole wheat flour
• ½ cup rolled oats
• 6 tablespoons unsalted butter, melted
• ¼ cup loosely packed light brown sugar
• ½ teaspoon vanilla extract
• ¼ teaspoon salt
• Bottom Layer:
• ½ cup unsalted butter, softened
• ½ cup confectioners' sugar
• 2 eggs
• 1 egg yolk
• 1 tablespoon lemon zest
• 1 ½ teaspoons finely chopped rosemary, or more to taste
• ½ teaspoon baking powder
• 2 (6 ounce) containers fresh blackberries

Step 1

Heat your oven to 350°F (175°C) and lining an 8-inch baking dish with parchment paper, letting the edges hang over two sides for easy removal later. In a small bowl, mix together the flour, oats, butter, brown sugar, vanilla, and salt with a fork until it looks crumbly—pop this in the fridge to chill while you work on the rest.

Step 2

Cream the butter and powdered sugar with a mixer until it’s light and fluffy. Beat in the eggs one at a time, plus the extra yolk, making sure everything is well combined. Stir in the lemon zest, rosemary, and vanilla extract for a fresh, fragrant touch.

Step 3

In another bowl, whisk the flour, baking powder, and salt. Gradually add this to your butter mixture, mixing well after each addition until you get a thick dough. Press the dough evenly into the bottom of your prepared pan.

Step 4

Scatter the blackberries all over the dough, then take the crumbly topping from the fridge, give it a quick stir, and sprinkle it evenly on top. Press down gently to help it stick together a bit.

Step 5

Pop the pan in the oven and bake for about 40 to 45 minutes, or until a toothpick poked into the center comes out clean. Once it’s done, let it cool on a wire rack for at least an hour.

Step 6

Finally, use the parchment paper edges to lift the bars out of the pan. Slice them into 12 squares with a serrated knife, and enjoy!