Put the whipped cream and cream cheese in the bowl and fold in the confectioners' sugar. Whip until fluffy.
Spoon the mixture into a piping bag and pipe some into each eggshell. Add a teaspoonful of lemon curd for the egg yolk.
Preheat the oven to 350ºf and line baking tin with parchment.
Combine the flour, sugar, and salt? add the butter and mix until the dough comes together. Press the mixture into the baking tin. Slice into rectangles, and bake for 30 minutes. Remove from the oven, re-cut the rectangles, and cool on a rack.