Line a tart or cake pan with parchment paper and grease well.

Combine the egg yolk from the separated egg, flour, powdered sugar, half of the vanilla extract, butter, cold water in a food processor and mix until a soft dough ball forms.

Fold the dough on a lightly floured surface. Fold it into itself, don't knead it like you would pizza dough. Use more water or flour depending on how sticky the dough is. This dough should be slightly sticky when you're done with folding.

Wrap the dough and refrigerate it for about 30 minutes. During this time turn on the oven to 400 degrees.

Once you take the dough out, roll it out, and move it to your pan. Working your way inside out, pat down the dough until you form edges. You want it roughly ¼ of the way up the sides.

Place the pan on a 9" baking sheet and bake at 400° for 20 minutes.

For the filling, combine the six eggs and sugar. Whisk, but be careful not to overdo it. Add in the heavy cream, lemon juice, lemon zest, and half a teaspoon of the vanilla extract and whisk to combine.

Pour in the filling into the baked crust and bake at 350° for 30-40 minutes. The center should be springy to the touch.

Serve warm or cold and serve with whip cream or powdered sugar. Both are also an option.