Special equipment: A large cookie sheet, well greased, or lined with parchment paper A 2-inch cookie cutter A small ice cream scoop, about 1 1/2 inches across A pastry bag fitted with a small plain tip (1/4-inch or less) A kitchen torch**
Pastry Bases: Mix the butter, flour, and salt until sandy in a mixer fitted with a paddle attachment. In a separate bowl, blend the yolk and creme fraiche. Add to the flour mixture and mix until barely combined. Form into a disk, wrap, and refrigerate at least 2 hours or up to 3 days.
Lemon Curd: Bring 2 inches of water to a simmer in a saucepan. Whip the eggs and sugar until light and fluffy in a mixer fitted with a whisk attachment. Add the lemon zest and juice and place the bowl over the simmering water (without letting the bowl touch the water; pour some out if needed). Cook until thickened, whisking occasionally, about 20 minutes. Remove from the heat and whisk in the butter. Let cool to room temperature, cover, and freeze overnight or up to 3 days.
Heat the oven to 375 degrees F. Flour a work surface and roll out the dough to 1/8-inch thick. Prick all over with a fork then cut out 2-inch rounds. Transfer to the cookie sheet. Bake until light golden brown, 10 to 15 minutes and let cool. (The whole recipe can be made up to this point up to 3 days in advance.)
Up to 6 hours before serving, assemble the dessert. Arrange the pastry rounds in a pan that will fit in your freezer (use two, if needed). Use a small ice cream scoop to place a ball or scoop of frozen lemon curd (it won't be frozen solid) onto each round. Place back in the freezer while you make the meringue. Meringue: Whip the egg whites until foamy, then add the sugar and continue whipping until stiff and glossy. Transfer to your pastry bag. Pipe meringue around the base of each pastry round, spiraling around and up the lemon curd ball and gradually enclosing the top to create a beehive. Fire up your kitchen torch and brown until lightly browned all over. Return to the freezer until ready to serve, up to 4 hours.
Consumption of raw or undercooked eggs, shellfish and meat may increase the risk of foodborne illness.
Propane gas torches are highly flammable and should be kept away from heat, open flame and prolonged exposure to sunlight. They should be used only in well-ventilated areas. Follow torch manufacturer's instructions for use.