Lemon Ice Cream Sandwiches with Blueberry Swirl

Everyone's free to be a kid again with one of these wickedly good frozen treats in hand. Chewy blondie cookies bookend a thick layer of lemony ice cream (store-bought vanilla bumped up with lemon juice and zest) ribboned with a speedy blueberry compôte.

Lemon Ice Cream:
2 pt premium vanilla ice cream
1 Tbsp. lemon zest, freshly grated
2 Tbsp. lemon juice, freshly squeezed

Blueberry Compôte:
2 cups blueberries (10 oz)
¼ cup sugar
2 (3x2½") strips lemon zest
1 Tbsp. lemon juice, freshly squeezed
2 tsp. cornstarch

Sandwich Layers:
1 cup all-purpose flour, unbleached
½ tsp. baking powder
¼ tsp. baking soda
¼ tsp. kosher salt
1 stick unsalted butter, softened
¾ cup light brown sugar, packed
1 large egg
½ tsp. pure vanilla extract

Special Equipment:
2 (8") square baking pans (2" deep); a small offset spatula

Make the Lemon Ice Cream:
Transfer ice cream to a microwave-safe bowl and microwave at 30 percent power in 10 second intervals, stirring, until softened, about 50 seconds total.

Stir in lemon zest and juice. Spread ice cream thinly in a 13x9" baking dish and freeze while making compôte and sandwich layers.

Make the Blueberry Compôte:
Cook blueberries, sugar, and zest in a 12" heavy skillet over medium-high heat, thoroughly crushing blueberries with a potato masher, until juices are released and sugar has dissolved, about 2 minutes.

Stir together lemon juice and cornstarch, then stir into blueberry mixture. Boil, stirring, 1 minute (mixture will thicken).

Transfer blueberry compôte to a bowl and chill until cold, about 1 hour. Discard lemon zest.

Preheat oven to 375°F (190°C/170°C fan, Gas Mark 5). Place an oven rack in middle of the oven. Butter baking pans and line with foil, leaving a 1" overhang on each side, then butter foil.

Make the Sandwich Layers:
Whisk together flour, baking powder, baking soda, and salt in a small bowl. Beat together butter and brown sugar in another bowl with an electric mixer at medium-high speed until pale and fluffy, about 3 minutes. Beat in egg and vanilla. At low speed, add flour mixture in 2 batches, mixing until just combined.

Divide batter between baking pans and spread into thin, even layers with offset spatula. Bake until golden-brown but still tender, 10-12 minutes. Cool completely in pans, about 30 minutes.

Assemble Sandwiches:
Dollop tablespoons of blueberry compôte all over ice cream, then swirl it gently through ice cream with a spoon. Spoon all of ice cream over 1 sandwich layer (in pan) and spread evenly using clean offset spatula. Invert second sandwich layer over ice cream, pressing gently to form an even sandwich. Wrap baking pan in plastic wrap and freeze until firm, at least 2 hours.

Transfer sandwich to a cutting board using overhang. Trim edges if desired, then cut into 8 pieces.

Cook's Notes:

• If you don’t have a microwave, ice cream can be softened at room temperature.
• Ice cream sandwich (before cutting) can be made 1 week ahead and frozen in pan, wrapped in plastic wrap and then in foil.