Place flour, salt, sugar and lemon zest together in food processor. Mix together and add butter. Pulse processor just until a dough is formed. If you have no processor, you can mix by hand, mixing quickly to get a shortbread dough. Refrigerate for 30 minutes.

Use a 9 or 10 inch tart pan that has removable bottom. Butter a piece of parchment paper and line bottom of pan, leaving a little overlap on the sides, so you can easily pull away.

Form in pan, prick with fork all over, and bake at 425 for 8 minutes. Turn heat down to 400 and bake another 4 minutes. Crust should be done at this point.

Heat cream and sugar, in small saucepan until sugar has melted and mixture is translucent.

Add extract, grand mariner and almonds. The optional pistachios add a bit of salt and added flavor that adds a nice touch. Allow to sit for 15 minutes, (although if you are in a hurry this is not completely necessary).

Pour into tart shell and bake for 25-30 minutes at 400 degrees.

During the baking process, check in at 15 minutes and tamp down any bubbles.

Remove from tart pan as soon as possible. Allow to partially cool to remove the bottom, but do remove it before the tart cools or it will stick to the bottom. I use buttered parchment paper on the bottom to counteract, and it works perfectly.