Step 1Mix the flour, sugar, salt and lemon peel. Cut the butter into half-inch slices and work it into the flour mixture with your hands or a pastry blender until the butter is mostly cornmeal-size pieces and the mixture begins to hold together; the softer your butter is, the faster this will happen.
Step 2Combine the water and the vanilla and work it into the flour-butter mixture just until the pastry is blended and will hold together if you press it. Gather it into a ball and wrap it in plastic. Let it rest for 30 minutes so the flour will absorb the moisture more completely.
Step 3Press the pastry into a 9-inch tart pan, making sure that you have a layer of even thickness over the bottom and the sides. If the thickness is uneven, some parts will bake too much before other parts are cooked. Set the shell in the freezer for 30 minutes or overnight, wrapped in foil.
Step 4Bake in a 375-degree oven for about 25 minutes, or until the shell is light golden brown and baked all the way through. Cool before filling.
Step 1Scald the milk -- that is, heat it to just under boiling. Mix the flour and sugar in a heavy non-corroding saucepan. Beat the egg yolks until thick and light colored, about 2 to 3 minutes in a mixer. Thoroughly whisk the hot milk into the mixed flour and sugar and cook over medium heat, stirring constantly, until the mixture has boiled for 1 minute or 2.
Step 2Whisk a little of the mixture into the egg yolks to warm them and stir back into the flour mixture. Mix well, being sure to incorporate all the flour mixture from the sides of the pan, and cook over medium heat, stirring constantly, until the pastry cream begins to hold a slight shape (170 degrees). It is important to cook the pastry cream thoroughly after adding the egg yolks, but don't let it boil. Cook until slightly thickened, about 10 minutes.
Step 3Remove from the heat and stir in the butter, then put through a medium-fine strainer. Cool and whisk occasionally to keep a crust from forming, or cover with plastic and refrigerate until cool, then whisk to smooth it out. Stir in vanilla to taste. Don't over-beat after cooking or the cream will thin out -- a useful thing to remember, because you can thin it, if it is too thick, by beating it. Beat it when cold, just before using, to smooth and thin slightly -- it should look shiny.
Step 1Shell the pistachios and toast them in a 350-degree oven for about 5 minutes, just long enough to bring out their flavor but not so long that they lose their green color. Cool them slightly, rub off their skins, chop them into one-sixteenth-inch to one-eighth-inch pieces and set them aside for the garnish.
Step 2Section the blood oranges into a small bowl, removing peel and membranes. Cover with their juice, cover tight and refrigerate if you are not making the tart immediately.
Step 3Put the sugar, butter and water into a small, light-colored saucepan and cook over medium heat until it becomes a light golden caramel, about 4 minutes. Pour it quickly into the bottom of the tart shell and swirl it over the bottom. It probably won't cover the bottom completely, but try to get an even covering by pouring the caramel in circles. This caramel makes a nice, crunchy texture contrast in the tart.
Step 4Stir a little Armagnac, Cognac or brandy into the pastry cream. Be careful not to beat it too much or it will thin out. Spread the pastry cream in a layer over the caramel in the bottom of the shell.
Step 5Dry the orange sections on a towel or paper towel, then arrange them over the pastry cream, overlapping the sections slightly. Begin from the outside of the tart and turn the sections in opposite directions in each successive ring. If the center is too small to make a final circle, fill it with small sections, perhaps in the form of a rose or an open flower. Sprinkle pistachios around the outside edge or around the center row of sections, or wherever you think they will look best.