MAKE THE CRUST:

1. MIX BUTTER, SUGAR & SALT: Add the butter, sugar, and salt to a stand mixer fitted with a paddle attachment. Mix at medium speed until smooth.
2. ADD EGGS: Mix in one egg and mix until combined. Repeat with the second egg. At low speed, combine the flour and mix until just combined.
3. FORM DOUGH & CHILL: Transfer the dough to a lightly floured surface. Divide into 4 balls and shape each one into a 1/2-inch thick disc. Wrap in plastic wrap and chill in the refrigerator for at least 2 hours or overnight. 

BAKE THE TART SHELLS:

1. ROLL OUT THE DOUGH: When the dough is ready, place it on a lightly floured surface, and using a rolling pin, roll the dough out until it’s 1/8 to 1/4-inch thick. Then, cut out circles of dough that are about 2 inches larger than the tartlet pans (to ensure the dough will also cover the sides of the pan). Add the dough circles to the tartlet pans, gently pushing into place. If it tears, just patch it with extra dough.
2. CHILL THE SHELLS: Next, place the tartlet shells into the refrigerator or freezer until the dough is firm, about 15 minutes.
3. BAKE THE TARTLETS: When ready to bake, preheat the oven to 325 degrees F. Then dock (prick) the bottoms with the tines of a fork. Then bake the tartlet shells until fully cooked and the crust starts to turn golden brown, about 10-12 minutes. Cool completely before using.
4. OPTIONAL EGG WASH: Use an egg wash to keep the crust crisp longer. Add it a few minutes before the shells are done baking, and then continue to bake until shells have reached their desired color.

COOK THE LEMON CREAM:

1. MIX TOGETHER LEMON JUICE, EGG, SUGAR & SALT: Pour about 2 inches of water into a saucepan and bring to a simmer. Whisk together the lemon juice, eggs, egg yolk, sugar, and salt in a stainless-steel or glass bowl that can fit safely fit over the saucepan without touching the water (like a homemade double boiler).
2. COOK THE MIXTURE: Cook the mixture while continuously whisking until the mixture is very thick, about 10-12 minutes. Remove from heat and let the mixture cool slightly.
3. BLEND IN THE BUTTER: Then add to a blender and add the butter, 1 tablespoon at a time, until fully incorporated. The mixture will be light yellow and thick. You can also use an immersion blender.
4. USE OR STORE: The lemon cream can be used immediately or stored in an airtight container in the refrigerator for up to 3 days. After refrigerating, just gently heat in a bowl set over simmering water until it is soft. 

ASSEMBLE:

1. Pour the lemon cream into the prepared tartlet shells. Shake the pans gently to even out the filling. Chill until firm, about 2 hours or up to 3 days.
2. MAKE WHIPPED CREAM: When ready to serve, whip the heavy cream until it thickens, then add the sugar and continue to whip until the cream holds stiff peaks.
3. GARNISH & SERVE: Add to the lemon tartlets, along with edible fresh flowers or any other garnish.