Blueberry custard squares

They taste just like pie, in an easy-to-serve format!

I was overwhelmed by the great response my blueberry cheesecake squares recipe received when I published it last year. Inspired by the love, I decided to take a fresh look at some of my favourite blueberry pie recipes; when a custard-based one caught my eye, I got busy experimenting with new twists. Note that these squares freeze well and for best presentation, it’s a good idea to trim the slab’s outer edges before cutting into serving pieces so each square is perfectly neat.

Ingredients

Crust and topping:

• 1 cup (227 g) salted butter, at room temperature
• 1/2 cup (100 g) granulated sugar
• 1 teaspoon lemon zest (or more, if you like)
• 2 cups (240 g) all-purpose flour
• 1/8 teaspoon salt
• 1/2 teaspoon freshly ground cardamom (or cinnamon)

Filling:

• 1 egg, at room temperature
• 2/3 cup (150 g) sour cream or plain Greek yogurt
• 1/2 cup granulated sugar
• 2 tablespoons (30 mL) freshly-squeezed lemon juice
• 1 tablespoon (8 g) all-purpose flour
• 4 teaspoons (10 g) cornstarch
• Pinch kosher salt
• 1 teaspoon vanilla extract
• 1/2 teaspoon freshly ground cardamom
• 3 cups (320 g) wild blueberries, fresh or frozen (do not thaw if using frozen)

Method

• Preheat oven to 350F. Line a 13 x 9-inch (32.5 x 22.5 cm) pan with parchment paper, leaving an overhang so you can lift the squares out of the pan after baking. Set aside.
• In a large bowl, beat butter, sugar and lemon zest until fluffy (use a stand or electric mixer if you have one). Scrape down sides of bowl then add flour, salt and cardamom and beat until just combined (mixture will be crumbly), scraping down sides of bowl again. Press about 2/3 of the mixture (approximately 2 cups) evenly into the prepared pan; set remaining 1/3 (approximately 1 cup) aside for topping.
• Bake crust for 15-17 minutes, until beginning to turn a light golden colour.
• While crust bakes, prepare filling. Put egg, sour cream, sugar, lemon juice, flour, cornstarch, salt, vanilla and cardamom in a medium sized bowl. Beat by hand or with a mixer until very smooth. Gently fold in 1 1/2 cups of the blueberries. Pour filling mixture over baked crust, tapping the pan a few times against the counter to settle the berries into the custard.
• Scatter remaining berries over top of the custard layer.
• With your hands, scatter reserved topping mixture over blueberry layer, pressing together as needed to ensure there are a few larger clumps of topping.
• Bake again until filling is set, about 30-35 minutes. Transfer the baking pan to a rack to cool completely then chill in the refrigerator for at least 1 hour.
• To serve, lift chilled squares out of pan using parchment paper ‘handles’. Use a large, sharp knife to cut into squares of desired size (I usually cut into 20 pieces). Refrigerate until serving. Leftovers freeze well.

Makes one large pan.