Preheat the oven to 325°F.
Stir together the graham cracker crumbs, granulated sugar, and salt. Pour in the melted butter and stir to combine so all the graham cracker crumbs are evenly coated. Press firmly into the bottom and sides of a 9” inch pie dish. Refrigerate while you make the filling.
1 3/4 cups graham cracker crumbs, 2 Tablespoons granulated sugar, Pinch of kosher salt, 1/2 cup unsalted butter
Slice the tops off of the muffins and reserve to eat separately. Slice the muffin bottoms in half again so you have two thin rounds (you should have 8 total). Place them on a sheet pan and lightly toast for 15 minutes, until the edges feel dry and the edges are golden.
2 4-count packs store bought coffee cake muffins
To make the pudding, whisk together the brown sugar, egg yolks, cornstarch, and salt in a bowl until smooth.
1/2 cup light brown sugar, 4 egg yolks, 1/4 cup cornstarch, 1/2 teaspoon kosher salt
Heat the milk and heavy cream in a saucepan over medium-high heat until steaming. Slowly pour about half into the egg and brown sugar mixture to temper it and slowly raise the temperature of the eggs so they don’t cook/curdle. Whisking constantly, pour it all back into the saucepan and cook over medium heat until it bubbles and thickens, 5-8 minutes.
2 cups whole milk, 1/2 cup heavy cream
Remove from the heat and immediately whisk in the cream cheese, butter, and vanilla until smooth. Run it through a fine mesh strainer if desired for an even silkier texture. Allow it to cool slightly.
8 oz cream cheese, 2 Tablespoons unsalted butter, 1 Tablespoon vanilla bean paste
Remove the pie crust from the fridge and pour 1/3 of the pudding in the bottom, spreading it to the edges. Add a layer of muffin bottoms, breaking up the pieces as needed so as much of the surface is covered as possible. Repeat with another 1/3 of the pudding and the remaining muffin bottoms. Top with the last 1/3 of the pudding.
Allow the pie to cool slightly so it isn’t steaming then press plastic wrap directly on the surface of the pudding and refrigerate for at least 6 hours, ideally overnight.
Before serving, make the crumb topping. Microwave the flour in a medium microwave-safe bowl in 30-second intervals, stirring between each, until the flour reaches 165°F throughout to heat treat it, since we aren’t cooking the pie. Let the flour cool. In a separate bowl, mix both sugars, the softened butter, cinnamon, and salt, then stir in the cooled flour until crumbly with some larger clusters.
1/4 cup light brown sugar, 1/4 cup granulated sugar, 1/4 cup unsalted butter, 1 teaspoon ground cinnamon, 6 Tablespoons heat treated flour
Remove the pie from the fridge and take off the plastic layer. Top the pie with the crumble. Whisk together the powdered sugar and milk and drizzle it over the pie. Cut into slices and serve chilled. Refrigerate for up to 2 days before serving.
1/2 cup powdered sugar, 1 Tablespoon milk