Banana Cream Pie

Steps

1. mix5 min
   by hand, fat left in flakes
   flour + crust salt + cold butter + shortening pinched to pea-size pieces, then + ice water a spoonful at a time until the dough just holds when squeezed — visible flakes of fat are what steam the layers apart later, so stop while you can still see them
2. rest60 min
   refrigerated, wrapped
   dough disc, until the fat is hard again and the flour fully hydrated — warm dough shrinks down the sides of the pan during the blind bake and you lose the wall you need to hold the custard
3. bake20 min
   400°F, lined with parchment and weighted
   rolled and chilled shell in a 9-inch pan, crimped and docked, filled to the rim with weights so the sides cannot slump inward
4. bake13 min
   400°F, weights and parchment removed
   shell until the base is dry, opaque and evenly golden, not pale — nothing in this pie ever cooks the crust again, so an underbaked bottom stays raw and goes to paste under a wet filling. Cool completely before filling.
5. simmer6 min
   medium, stirring, just to steaming
   milk + custard cream + half the sugar + custard salt, until it steams at the edges and the sugar has dissolved
6. whisk2 min
   until pale and smooth
   egg yolks + cornstarch + remaining sugar, until no dry starch pockets remain — lumps at this stage never dissolve later, they cook into hard specks
7. temper3 min
   hot dairy added in a thin stream, whisking constantly
   yolk-starch mixture + about a cup of the hot dairy, then the rest, so the yolks climb in temperature gradually. Dumping hot dairy in all at once sets the proteins on contact and gives you sweet scrambled egg you cannot whisk back out.
8. boil1 min
   full rolling bubbles, whisking without stopping, timed
   combined custard returned to the pot over medium heat, whisked into the corners, until it thickens and then bubbles — and held at that boil for a full minute. This is the step the pie lives or dies on: cornstarch only reaches full thickening power at a boil, and starch pulled off early both sets soft and tastes raw and pasty. A minute past the first bubble, then stop; over-agitating finished pastry cream breaks it thin again.
9. mix3 min
   off the heat, then strained
   + finishing butter + vanilla stirred until glossy, then push through a fine sieve to catch any set egg = pastry cream
10. top8 min
    warm custard, working quickly
    cooled shell + a thin layer of pastry cream spread to the crimped edge + banana slices in a single overlapping layer + remaining pastry cream sealed over and around them, right to the pastry wall. Fully enclosed bananas have no air contact and brown far more slowly; fruit left exposed on top of the custard greys within hours. Pouring the custard warm gives the tightest seal against the crust.
11. store240 min
    refrigerated, plastic pressed directly onto the surface
    assembled pie until fully set and cold through — contact covering is not neatness, it is what stops a rubbery skin forming as the surface dries. Four hours is the working minimum; overnight is better and slices cleanest.
12. whisk4 min
    cold cream and bowl, to soft-medium peaks
    topping cream + powdered sugar, stopping while the peaks still fold over — then spread over the chilled pie within an hour of serving, since whipped cream put on early weeps water onto the custard