Lemon Meringue Pie Bars (Print Version)

# Ingredients:

→ Shortbread Base

01 - 2 1/4 cups (225g) shortbread cookie crumbs
02 - 3 tablespoons unsalted butter, melted

→ Lemon Layer

03 - 1 1/2 cups granulated sugar
04 - 1 small pinch of salt
05 - 1/2 cup freshly squeezed lemon juice (from 3-4 lemons)
06 - Zest of 1 medium lemon
07 - 4 large eggs, at room temperature

→ Marshmallow Topping

08 - 4 large egg whites, at room temperature
09 - 3/4 cup granulated sugar
10 - 1 pinch of cream of tartar (optional, for stability)

# Instructions:

01 - Preheat oven to 350°F (175°C). Line a 9-inch square baking pan with aluminum foil and lightly coat with cooking spray. Combine cookie crumbs and melted butter in a bowl until moistened. Press mixture firmly into the pan bottom. Bake for 14 minutes until edges are slightly golden.
02 - Whisk sugar, salt, and lemon zest in a bowl. Add lemon juice and eggs, whisking until smooth. Once the crust is baked, pour the filling over it. Bake for 18-22 minutes or until the filling is set at the edges but slightly jiggly in the center. Cool at room temperature, then refrigerate for at least 3 hours.
03 - Bring 2 inches of water to a simmer in a saucepan. In a heatproof bowl over the saucepan, whisk egg whites and sugar constantly for 5-7 minutes until the mixture reaches 140°F (60°C) and sugar dissolves. Transfer to a stand mixer and beat on medium-high for 5-7 minutes until thick, glossy peaks form.
04 - Lift the chilled bars from the pan using foil overhang. Spread meringue over the top, shaping peaks and swirls. Use a torch to lightly toast the meringue or broil for 1-2 minutes while watching carefully. Slice into squares with a hot, clean knife and serve immediately.

# Notes:

01 - For stronger lemon flavor, rub zest into sugar before mixing.
02 - The double-boiler method for the meringue ensures a stable topping.
03 - Watch closely when browning under the broiler to avoid burning.
04 - Graham crackers can replace shortbread in the crust, but use 5 tablespoons of butter instead.