Make the Crust:

1. Preheat the oven to 300°F.
2. In a mixing bowl, combine the graham cracker crumbs, dark brown sugar, coconut shreds, and cinnamon. Mix in the browned butter and stir until everything is well combined, and the crumbs are all thoroughly moistened.
3. Pour half of the crumb mixture into a 9″ springform pan lined with parchment paper. Use the bottom of a dry measuring cup to gently but firmly press the crumbs down into the bottom of the pan in an even layer.
4. Pour the remaining crumb mixture in and use the measuring cup to press it up along the sides of the springform pan.
5. Beat together the egg white and water. Pour the egg was into the crust and use a basting brush to brush the egg wash all over the crust, up the sides and everything. This will prevent the filling from making the crust soggy.
6. Bake the crust for 20–25 minutes, until the coconut is fragrant, and the crust is slightly deepened in color. Remove from the oven and let rest on the counter until cooled.

Make the Key Lime Filling:

1. Make sure an oven rack is located in the very center of the oven, then preheat it to 300°F again.
2. In a large bowl (or the bowl of your stand mixer affixed with the whisk attachment) beat together the sweetened condensed milk, egg yolks, lime juice, and lime zest, just until combined. Whisk in the green food coloring, if using, until no streaks remain.
3. Pour the filling into the cooled graham cracker crust. Transfer the springform pan to a baking sheet. Bake the pie for 27–30 minutes, until the middle has set, but the outer edges of the pie still jiggle when you tap the side of the pan.
4. Remove from the oven and let rest on the counter, covered loosely, until it comes to room temperature.

Make the Whipped Key Lime Topping:

1. In a medium-sized mixing bowl, beat together the sweetened condensed milk, cream cheese, mascarpone, lime juice, and sugar until no lumps remain.
2. Use a silicone spatula to fold in the whipped cream, gently mixing until there are no streaks.
3. Dollop the cream mixture on top of the cooled pie and use an off-set spatula to spread it out into an even layer from edge to edge. It’s up to you if you let it overlap the top of the crust (I did, a little).
4. Sprinkle the lime zest all over the top of the pie, covering it lightly and evenly.
5. Cover the key lime pie and refrigerate it for at least 8 hours. Garnish with whipped cream, lime slices, raspberry sauce, whatever you like. Dassit!