Peel and slice the apples. Heat the butter in a wide pot over medium high heat. Add the apples along with the sugar, cinnamon, nutmeg, allspice, salt, and lemon juice. Stir to combine.

Cook the apples, stirring occasionally, just until they are softened and begin to release their juices. They should be softened but still hold their shape.

Transfer the apples and their juices to a dish and spread them out to cool before refrigerating.

Make the pie crust in a food processor. Pulse flour and salt, add diced butter, then pulse until it resembles small peas.

Pour in ice water while pulsing until the dough sticks together. Form into a large ball, divide, and chill for at least an hour.

Melt butter in a small saucepan, whisk in brown sugar, then heavy cream until emulsified.

Bring to a boil for 1-2 minutes, then cool.

Preheat oven to 350°F. Roll out the larger disc of dough and fit it into a greased pie plate.

Spoon half of the apple mixture and drizzle half of the toffee sauce over. Repeat with the rest.

Roll out the second disc and create a lattice crust or place it whole over the filling. Trim and crimp edges.

Brush with egg wash, then bake for 50-60 minutes until filling is bubbling and crust is well browned. Cool before slicing.

In a bowl, whisk together egg yolks, sugar, cornstarch, and salt until lightened.

Heat milk, then temper it into the egg mixture gradually. Return to saucepan and cook while stirring until the custard thickens.

Add butter and vanilla, strain, cover with plastic wrap on the surface, and cool.

Serve slices of the Toffee Apple Pie with vanilla custard drizzled over.