Step 1

Make the crust: Preheat the oven to 350 degrees F. Brush the bottom and sides of a 9-inch pie dish with some melted butter and set aside.

Step 2

In a medium bowl, combine the graham cracker crumbs, sugar, cinnamon, ginger, a pinch of salt and the rest of the melted butter. The texture should resemble wet sand. Use the bottom of a glass or measuring cup to press the crust into an even layer on the bottom and up the sides of the prepared pie dish. Place the dish on a sheet pan and bake until the crust firms and browns lightly, 10 to12 minutes. Remove from the oven and let cool.

Step 3

Make the filling: In a medium bowl, combine the condensed milk, sour cream, grapefruit juice, lime zest and lime juice.

Step 4

Bake the pie: Pour the filling into the crust and jiggle the dish to smooth evenly. Place onto a sheet pan and bake in the center of the oven until firm, 18 to 20 minutes. Let cool on a wire rack for at least 2 hours. Chill in the fridge.

Step 5

To serve: Cut the pie into wedges and serve with grapefruit segments and whipped cream if desired.