If you want you make these as sandwich cookies make the Meyer Lemon Curd the day before so it has time to set up and chill. Times are approximate for prep, baking, making the buttercream and assembly. Sift the flour, corn starch, confectioners sugar and salt into a medium bowl.
300 g All purpose flour, 2 Tablespoons Corn starch
, 100 g Confectioners sugar, ⅛ teaspoon Kosher salt
In a larger bowl or stand mixer, cream the softened butter then add the vanilla sugar, egg yolks and the lemon zest and mix until combined.
Add in the flour mixture and mix again until combined. Do not overmix.
175 g 175 g unsalted butter, 1 packet vanilla sugar, 2 large egg yolks, 3 Tablespoons Meyer lemon zest
Form a ball with the dough, wrap it in plastic wrap and put it in the fridge for 30 minutes.
Preheat the oven to 350°F/180° c and line baking sheets with parchment paper.
Roll out the dough to a thickness of 3-5 mm between 2 sheets of parchment paper or wax paper (the dough sticks slightly) then cut out the shapes with a cookie cutter.
Pro Tip - Chill the dough in the freezer for just a few minutes when rolled out then again after cutting out shapes so they lift out easier due to being a sticky dough and so they don’t spread when baking.
Arrange the cut out cookies on the prepared pan, put in the oven and bake them for 10 minutes. (You will glaze them at 9 minute then bake for another minute) While they are baking make the lemon glaze by whisking together the confectioners sugar, lemon juice and salt until smooth and no lumps are left.
100 g confectioners sugar, 1-2 Tablespoons Meyer lemon juice, Pinch kosher salt
Take the tray out of the oven and quickly glaze the cookies with brushing on the lemon glaze. Pop them back in the oven for another minute.
Remove from the oven and let cool for a minute or two, transfer to a wire rack to cool completely.
While they are cooling make the buttercream then finish making the sandwich cookies.
Make the lemon Italian meringue butter cream:
Whip egg whites, cream of tartar and 60 g sugar and salt on low until foamy - keep mixer running on low
2 large egg whites, ¼ teaspoons cream of tartar, 60 g granulated sugar, ½ teaspoon salt
Mix 100 g sugar with 50 g water in sauce pan and bring to boil after sugar dissolves, stirring until the sugar is dissolved
100 g granulated sugar
Heat to 240 Deg F. Using a clip on candy thermometer
The egg whites should be at soft peaks by the time the sugar syrup reaches 240 F. Carefully pour the sugar syrup into the mixer avoiding the whisk and sides of the bowl as best as you can
Whip until the bowl is cool. See below if torching the meringue. Do this before adding the butter.
Switch to paddle attachment. Add in soft butter one tablespoon at a time. Add in vanilla. Mix until smooth and thick.
200 g butter, ½ teaspoon vanilla extract
Transfer to a piping bag fitted with a small open star tip and pipe a circle onto one half of the bottom of a cookie, fill center with a teaspoon of lemon curd. Sandwich together with another lemon cookie. Keep chilled and bring to room temp before serving.