"That bottom layer? Magical...."
Cooking spray, for pan
(1 stick) butter, cut into tablespoons
granulated sugar
Dutch processed cocoa powder
large egg, beaten
pure vanilla extract
(1½ sleeves, crushed) graham cracker crumbs
unsweetened shredded coconut
finely chopped toasted pecans
kosher salt
butter, softened to room temperature
custard powder or instant vanilla pudding mix
powdered sugar
kosher salt
heavy cream
dark chocolate chips
butter
Flakey sea salt