This is a pie like you have never had before. It is light and creamy, everything you could want in a comfort food pie. The recipe comes from my mother-in-law who emmigrated to the U.S. from Japan in 1968. She was a talented cook, who learned American cooking from her neighbors on Long Island. As a scientist, her methodology in the kitchen reflected her lab. When she passed away last year, we found stacks and stacks of her kitchen "lab notebooks". This recipe is one of the family treasures! I use the Cooks Illustrated pie crust recipe here, but feel free to use your own or even a frozen Trader Joe crust.
makes one pie
1 3/4 cups
vegetable shortening, cold and cut into pieces
unsalted butter, cold and cut into pieces
large sweet potato, preferably Japanese Satsuma (14 oz)
Crust: Combine salt, sugar and 3/4 cup flour in the bowl of a food processor and short pulse once or twice to mix. Add butter and shortening and use longer pulse to mix until dough resembles cottage cheese curds, 6-7 two second pulses. Scrape down sides. Add remaining 1/2 cup flour and pulse until dough is mixed and flour is incorporated - 3-4 pulses. It will still be pretty chunky. There may be visible pieces of butter, but his is ok.
Turn dough into mixing bowl. (Make sure to scrape out processor bowl as much as possible, but no need to wash as we will use it again, in a bit.) Sprinkle water and vodka over the dough. With a rubbefr spatula, fold and press dough until it comes together, but is pretty tacky. Flatten dough into 4 inch disk and refrigerate 45 minutes or up to 2 days.
Remove dough from refrigerator and roll out on a floured surface. Roll to 1/8" thick and diameter of 12 inches. Roll dough loosely onto floured rolling pin and unroll over pie dish. Lightly press dough into pie pate. Leave 1" overhang and cut excess with scissors or knife. If dough is getting soft, return pie plate to refrigerator for 15-20 minutes or continue. Trim overhang to 1" around the plate. Tuck the ends under and flute the edges by pinching or using a fork. Use a fork, to put Refrigerate again for 15 minutes.
Filling: Turn oven to 425F. Cut sweet potato into 4 or 5 sections. Steam, microwave or bake until tender. (I use a pressure steamer and it takes about 15 minutes). Drain and let cool until they can be handled comfortably.
Meanwhile combine milk, cream, vanilla, salt and eggs and beat to combine.
Peel sweet potato. In a large mixing bowl, mash sweet potato until smooth. You can use a ricer or a food mill. Add wet ingredients and mix until just combined. Pour ingredients into the food processor and pulse for 5-10 seconds. You want a very smooth, pourable batter. If you don't want to use a food processor, like my mother-in-law who liked to do things by hand, you can send the batter through a fine sieve, pushing the batter through with a spatula. This helps make the pie velvety smooth!
Remove pie plate from refrigerator. Pour batter into pie shell to slightly under the brim. The pie will poof slightly in the oven. Turn oven down to 350F and put pie into oven. Cook for 45 minutes or until a test skewer comes out clean.