Pumpkin spice latte sweet potato pie

Cut nine tablespoons of butter into thin pats, toss with a little flour and freeze with two identical metal pie pans for at least 15 minutes.

Pulse 165 g all-purpose flour with 3 g kosher salt in a food processor to combine.

Add the chilled butter and pulse to small pebbles, about ten one-second pulses.

Drizzle in 65 g of very cold water while pulsing a second at a time, about five pulses.

Turn out onto plastic wrap, draw it up, squeeze the dough into a ball, flatten to a one inch disc and refrigerate 30 minutes.

Roll the dough between two floured sheets of parchment to an eighth inch thick circle, just over 11 inches across. If it is too firm, let it sit five minutes, but no longer or the fat goes oozy.

Invert one chilled pan, lay the dough over it, press the second pan on top to shape it, flip the whole thing, remove the top pan and peel the parchment.

Trim the excess dough, put the top pan back on and freeze at least 30 minutes, or overnight.

Position a rack in the centre of the oven with a second rack beneath it holding a sheet pan to catch fat, and heat to 300.

Bake the pan-dough sandwich inverted on the top rack about one hour, until the crust just begins to set.

Raise the oven to 375 and bake another 20 to 30 minutes until the edges turn deep gold; start checking at 20 minutes, and expect 30 to 40 with light metal pans.

Remove, flip right side up, take off the top pie pan and cool completely on a rack.

Raise the oven to 400 and roast the sweet potatoes until very soft, about an hour, then cool until peelable.

Turn the oven down to 350.

Peel the cooled sweet potatoes with your fingers into the mixer bowl and mix on medium to medium high for one minute with the paddle.

Scrape down, work in the brown sugar on low, then the cream, the eggs and finally the spices and salt; beat on low another minute just to incorporate.

Press the mixture through a wide fine mesh strainer over a bowl with a spatula and then a bowl scraper — not to strain it but to break up small fibres — and scrape the underside of the sieve.

Fill the baked crust and smooth with an offset spatula.

Bake at 350 until the pie just jiggles slightly in the centre and reaches an internal temperature of 165 to 170, about 40 to 45 minutes.

Rest one hour on a rack, then cover and refrigerate overnight; he prefers it cold.

Whip 240 g heavy cream, 13 g 10X confectioners sugar, 15 g coffee liqueur, a quarter teaspoon of instant espresso powder and one to two drops of vanilla to medium peaks, and spoon on top.