Many of the steps seem very time-consuming and impossible if you are planning dinner or other treats for guests, but you can prepare the tart shells and pastry cream a day or two in advance and quickly assembly the tartlets the day you wish to serve them. Once assembled, they are best that day.
If you don't have access to small tart molds or a tart pan, you can use muffin pan or make a larger, regular-sized tart (like in 9" or 10" pan). Baking times will vary with different size molds and pans. My tart molds are 3", but if you are making tartlets with something else, I'd just watch them carefully. For a larger tart pan, you would also want to use weights when baking, which you can purchase or tie together some cheesecloth filled with dry rice or dried beans.
Makes 24 tartlets, using 3" tart molds.
Step 1: The Crust
In my pictures, it shows the ingredients doubled from my recipe, as I like to have a standby crust in the refrigerator or freezer for when I next feel like making a tart. If you want to do this, when making the disc of dough, simply divide the dough in half first and make 2 discs. You can store the extra dough in disc or rolled-out form in the refrigerator for 3 days (freeze if using after that point, and let thaw in the refrigerator for an hour before using).
I show in the pictures how I store the extra tart dough after rolling it out. Place plastic wrap over it, and roll it up so that the plastic wrap is between each layer of dough. Wrap another piece of plastic wrap around this, folding in the ends and refrigerate.
1 cups all-purpose flour
2 Tbsp. granulated white sugar
1/2 tsp. salt
1/2 cup cold butter, cut into small pieces (leave in refrigerator until needed)
1 egg yolks
1/8 - 1/4 cup heavy whipping cream
1/2 tsp. vanilla extract
1 Tbsp. lemon juice
Whisk together the egg yolks, 1/8 cup heavy whipping cream, vanilla extract and lemon juice in a small mixing bowl. In a medium mixing bowl, add together the flour, sugar and salt. Put both bowls in refrigerator for about 30 minutes.
Put the dry ingredients in the food processor and pulse to combine (or if a food processor is not an option, mix it by hand). Add the butter and pulse (or cut in with a pastry blender) until texture resembles course crumbs. Put the mixture back into the medium mixing bowl and pour the liquid ingredients over it. Stir just until combined. If dough doesn't pinch together easily add up to another 1/8 cup of heavy whipping cream a tablespoon at a time until it does pinch together.
Form the dough into a disc and plastic wrap it. Refrigerate for at least 2 hours (use within 3 days).
If your tart molds (or pan) are not non-stick, butter or grease them otherwise.
Place the disc onto a well-floured work surface (tart dough is very sticky). Flour the top of the disc and the rolling pin generously. Roll the dough out so you have about a 12" diameter. Roll from the center out, and rotate the dough occasionally to avoid sticking.
Gently place your tart mold onto the rolled out dough. Using a knife or clean razor blade and leaving a 1/4" border, cut around the mold. Transfer the cut-out to the mold, gently pressing in the corners (do not stretch the dough). Press the dough overhanging the edges of the mold down to cut off the extra dough. Retain the extra bits of dough to ball up and re-roll out. Do the same for the rest of the tart molds. If you run out of dough but still have some molds to fill, now is the time to roll out the extra dough. Just remember to minimize the number of times you do this, as over-worked dough bakes tough.
Place the molds onto a parchment-lined cookie sheet and refrigerate for about 30 minutes. In the meantime, preheat the oven to 375 degrees Fahrenheit.
Poke the bottom of each crust a couple times (or more, if using a larger mold or pan) with a fork, and bake for 10 - 12 minutes until lightly golden. As mentioned before, baking times will vary with different sizes of tart molds and pans. Watch them carefully!
Cool completely. If the tart crusts don't want to just slide or pop right out of the mold, gently drop them upside down onto a clean surface. This should be enough to get them to just fall right out. If not, very gently use a knife to loosen the edges.