> Cooking spray
> 1 cup gluten free flour blend
> 1 1/4 cups sugar, divided
> 1/4 tsp salt
> 1/2 cup (1 stick) cold butter, diced
> 3 lemons
> 2 large eggs
> 2 tbsp gluten-free cornstarch
Preheat oven to 350°F. Coat an 8x8-inch baking pan with the cooking spray.
In a food processor, pulse the flour blend, ¼ cup sugar, and salt to combine. Pulse in the butter and 3 tbsp water until mostly incorporated, stopping and stirring mixture occasionally. Pat dough into the bottom of baking pan. Bake 20 min., until dry to the touch and set.
Into a medium bowl, grate 1 tbsp zest and squeeze ½ cup juice from the lemons. Whisk in the eggs, cornstarch, and remaining 1 cup sugar until smooth. Pour lemon mixture directly over the warm crust.
Bake 15–20 min., until filling is set. Cool completely on wire rack before cutting into bars.