The goal: a pi-shaped pie for Pi Day. But how?
Step 1: Template
First, draw a nice, fat pi on a piece of paper and cut it out.
Step 2: Form Mold
Then, tack the template onto a block of florist's foam (easier to cut than styrofoam) and cut out the shape.
Step 3: Fabricate the Pie Pan
Now it's time to create a custom pie pan. As neatly as possible, line the negative shape with several layers of heavy duty aluminum foil.
Step 4: Creating the Crust
Using a pie dough that is easy to work with,* roll it out into three pieces that more or less correspond with the three parts of the pi shape. Lay the rolled dough into the mold and gently heal the seams with your fingers. Neaten the top edge of the crust being careful not to squish it into the foil, as this will make it nearly impossible to get free after it bakes. Also, you may want to line the top of the florist's foam with plastic wrap so you don't incorporate any foam bits into the dough as you work.
Once the mold is neatly lined with pie dough, remove it from the foam. The safest way to do this is to break the foam apart.
*I used a double recipe of the prebaked pie shell from Cook's Illustrated Best Recipe, paraphrased here:
1 1/4 c. all-purpose flour
1/2 tsp. salt
1 Tbsp. sugar
4 Tbsp. butter, chilled cut into pieces
3 Tbsp. vegetable shortening
4-5 Tbsp. ice water
Mix dry ingredients in the bowl of a food processor. Add butter and shortening and pulse until the pieces are no bigger than small peas. Turn into a bowl, sprinkle with 4 Tbsp. water and mix until the dough comes together, adding more water as needed. Knead once or twice until it forms a uniform ball. Flatten into a disk, wrap with plastic and refrigerate for at least 2 hours. Let stand for 10 minutes at room temp before rolling.
Bake at 375.
Step 5: Blind Baking
Set the dough-lined mold into a large, high-sided pan (this is my monster cake pan). Then, fill in all around the pie with rock salt. Be very careful not to let the salt get into the pie crust or in between the pie crust and the foil--no one wants a chunk of rock salt in their pie!
Now line the inside of the dough with foil or parchment and fill that with rock salt. (Pie beans would work fine here, too. I just didn't have enough).
Now the pie crust is ready to blind bake. This step will set the dough so that it keeps its shape and doesn't slump.
Bake at 375 for 20-25 minutes. Baking the crust takes longer than usual because the rock salt creates insulation.
Step 6: Finish Baking
Once the dough has begun to bake, take the pan out of the oven and remove the interior parchment and rock salt. Again, be careful not to let any of the salt drop into the crust.
Return the crust to the oven for another 20 minutes or so, until it has begun to turn a bit golden and is cooked through. Then remove it from the oven and let it cool completely before proceeding.
Step 7: Fillling the Pie
Once the crust has cooled, fill it. Use something delicious that will set up firmly. I went with chocolate cream stabilized with egg yolks and corn starch, and made extra special with some St. George Spirits Firelit coffee liqueur. But coconut cream, lemon, or grasshopper would all work beautifully.
Pour the warm filling into the pie crust, still in the bed of rock salt, and place the whole thing in the refrigerator for at least 4 hours. You want it to be really, truly firmly set up before you move on to the next step.
Chocolate Cream Filling
2 c. half and half
5 Tbsp. sugar
6 egg yolks
2 Tbsp. cornstarch
6 Tbsp. butter
6 oz. bittersweet chocolate, chopped
1 oz. unsweetened chocolate, chopped
2 tsp. vanilla
1/2 c. St. George Spirits Firelit liqueur (I'm not being a snob here. St George basically swapped the ratio of coffee to sugar in their spin on Kahlua, so if you use Kahlua cut back on the sugar.)
Warm half and half with 2 Tbsp. of sugar and the salt. Whisk together egg yolks, 3 Tbsp. sugar, and cornstarch being sure to whisk until any lumps are gone. Whisk some of the warm half and half into the yolks to temper, then return the warmed yolks to the pan with the half and half and continue whisking over medium heat until the mixture begins to thicken. Turn off the heat and add the chocolate, vanilla and liqueur. Stir until smooth and immediately pour into the prepared Pi shell.
Step 8: Unmolding
This is probably the trickiest step of the whole operation. Very, very gently lift the pie and the foil pan out of the rock salt and set it on your serving tray. An extra set of hands can be really useful here.
(Note: I created a tray with a piece of cardboard and aluminum foil since I didn't have a flat tray large enough to hold my Pi.)
Slowly, gently and carefully peel the foil back and, lifting the pie gently bit by bit, slide the foil out from underneath.
Watch out for the ever-hopeful furry vultures.
Step 9: Finished!
Now it just needs a little decorating and you're all ready to serve.