Food Processor Method
Process the lemon zest with the sugar and salt until the zest is very fine.
Cut the butter into several pieces and add it with the motor running. Process until smooth and creamy,
Add the egg and vanilla and process until incorporated, scraping the sides of the bowl as needed.
Add the flour and pulse in just until incorporated. The mixture will hold together if pinched.
Electric Mixer Method
For the best texture use superfine granulated sugar.
Soften the butter and chop the lemon zest until very fine.
In a mixing bowl cream together the sugar and butter until fluffy. Add the lemon zest, egg, and vanilla extract and beat until blended.
In a small bowl, whisk together the flour and salt. On low speed, gradually add it to the butter mixture and mix until incorporated and the dough just begins to come away from the sides of the bowl.
For Both Methods
Scrape the mixture onto a large sheet of plastic wrap and use the wrap to press down on the dough, kneading it until it is smooth. Divide the dough into four pieces, wrap each one with plastic wrap, and press to form flat discs. Refrigerate for 2 hours up to 2 days placed in a zip-seal bag, to firm and give the dough a chance to absorb the moisture evenly to make rolling easier.
Lemon Neoclassic Buttercream
Makes: 1 cup/about 8 ounces
2 large egg yolks
1/4 cup superfine sugar
2 tablespoons light corn syrup
8 tablespoons (1 stick) unsalted butter, softened—65 to 75°F
1 tablespoon lemon zest, finely chopped, loosely packed
2 tablespoons lemon juice, freshly squeezed
1/2 teaspoon pure vanilla extract
