Strawberry-Rhubarb Margarita Bars
Makes one 8-inch square pan
Serves 9 to 16
For the filling:
1 pound (454g) strawberries, stems removed
1/2 pound (227g) rhubarb, chopped and leaves removed
1/2 cup (120ml) tequila of your choice
3 large eggs
3/4 cup (140g) granulated sugar
1/4 cup (30g) powdered sugar, plus more for garnish
3 tablespoons (24g) all-purpose flour
2 tablespoons lime zest (3-4 limes)
For the crust:
1/2 cup (113g) unsalted butter, at room temperature
1/4 cup (50g) granulated sugar
1/4 cup (30g) powdered sugar
1 tablespoon lime zest (about 2 limes)
1/4 teaspoon salt
1/8 teaspoon freshly ground black pepper
1 cup (120g) all-purpose flour
Preheat the oven to 350°F/177°C. Line an 8-inch square baking pan with two overlapping sheets of parchment, with the paper overhanging the sides, creating a sling to lift the bars out later. Set aside.
Place the strawberries and rhubarb in a food processor or blender, and purée until smooth and liquified. Strain the mixture through a nut-milk bag, several layers of cheesecloth, or an ultra-fine-mesh strainer to remove all seeds and pulp. You should have about 2 cups of juice. Pour the juice in a small saucepan and add the tequila. Set the pan over medium-low heat, bring to a gentle simmer, and cook until the liquid reduces to just 1/3 cup of thick syrup, stirring occasionally, about 45 to 55 minutes. If the mixture begins to foam up, lower the heat to a more gentle simmer. When the mixture has reduced to 1/3 cup, pour it into a heatproof measuring cup and chill in the fridge for 10-15 minutes before use.
Meanwhile, as the juice mixture is simmering, make the crust: in a mixing bowl, beat the butter until light and creamy. Add the granulated sugar, powdered sugar, lime zest, salt, and pepper, and beat until fluffy and smooth. Add the flour and beat until just combined. Transfer the dough to the prepared baking pan and use your fingers to press it into an even layer over the bottom of the pan, about 1/4 inch thick. Bake for 15-18 minutes, until the edges just begin to turn brown. Remove from the oven and allow to cool briefly.
While the crust is cooling, finish making the filling: in a mixing bowl, whisk together the eggs, granulated sugar, and powdered sugar until smooth. Add the cooled juice mixture, flour, and lime zest, and whisk to combine. Pour over the warm crust and bake until the center is set and the edges begin to brown, 25 to 30 minutes. Place the pan on a cooling rack and cool completely. Then cover the pan with foil or plastic wrap, and refrigerate until chilled, at least 2 hours or overnight.
Cut into squares—either 9 large squares or 16 smaller ones—then dust with additional powdered sugar and enjoy!