- 2 4.9 ounce packages Walkers Gluten Free Ginger and Lemon Shortbread
- 1/3 cup melted butter
- 1 large egg (optional)
- Lemon Curd
- 6 large lemons, zested and juiced
- 1 1/2 cups fine white sugar (also known as baking sugar)
- 3 ounces (6 tablespoons) unsalted butter, a bit softened
- 6 large eggs
- 6 large egg yolks
- 1/2 teaspoon kosher salt
Make the shortbread crust.
Pulse the shortbread cookies in the bowl of a food processor until they are crushed into crumbs.
With the food processor running, add the melted butter until the mixture comes together. (If you feel the crumbs just aren’t holding together enough, you can add the egg.)
Pat the mixture into a 10-inch tart pan with a removable bottom. Using your fingers or the back of ramekin, gently press the shortbread crumbs together in the pan. Even off any stray bits at the top of the tart pan.
Bake in a 350° oven until the tart crust was firm to the touch and starting to get a bit of color on it, 8 to 10 minutes. Take it out of the oven and let it cool.
Make lemon sugar for the lemon curd. Add the lemon zest and sugar to the bowl of a stand mixer. Mix until they are clumping together and smell like a bright winter day, about 5 minutes.
Cream the butter and sugar. Add 4 tablespoons of the butter to the lemon sugar. Run the mixer until the butter and sugar are combined thoroughly and are fluffy, about 5 minutes.
With the mixer running, add the eggs one at a time, then the yolks one at a time. Pour in the lemon juice and mix, then the salt. The mixture should be a thick liquid, quite yellow and coherent.
Cook the lemon curd. Pour the liquid into a large pot set over medium heat. Cook, stirring frequently, until the liquid thickens. At first, you might think it will never happen. Keep stirring, constantly at this point, to avoid curdling.
After 10 minutes or so, the curd will suddenly thicken, pull away from the edges of the pot a bit, and bubble vigorously. (You can also use a candy thermometer to take the curd to 170°.) Stick a spoon into the curd. When you drag your finger down the back of the spoon, does it leave a clean trail? You’re done. Pull the pot off the heat.
Add the remaining 2 tablespoons butter to the lemon curd and stir until the mixture is smooth (emulsified).
Strain the curd through a fine-mesh sieve to remove the zest. (Skip this step if you don’t mind the bits of zest on your teeth.)
Refrigerate the lemon curd until it is cold.
Finish the lemon tart. Gently spread the cold lemon curd into the crust. Smooth out the top with a rubber spatula.
Chill the tart in the refrigerator for at least 1 hour.
Working slowly, push up on the bottom of the tart pan to separate the tart from the pan. Serve.