• Arrange an oven rack in the center position and preheat the oven to 350°F. Spray a 9-inch pie plate with cooking spray.

Prepare the crust:

• In a food processor, pulse the crackers, sugar, salt, and ginger, if using, until very finely ground. Pour in the melted butter and pulse until combined. The mixture should look like wet sand.
• Transfer the mixture to the pie plate. Press firmly into the bottom and up the sides of the pan. Bake until the crust is fragrant and firm to the touch, 8 to 10 minutes. Remove from the oven and place on wire rack to cool slightly while you make the filling.
• Turn the oven down to 325°F.

Prepare the filling:

• In a large bowl, combine the filling ingredients, whisking until smooth. Pour the filling into the prepared crust and smooth the surface. Bake at 325°F until the filling is set and just a little wobbly in the center, 25 minutes. Remove from the oven and let cool completely at room temperature. Transfer to the refrigerator and chill until cold, at least 4 hours. Cover with aluminum foil or plastic wrap if chilling overnight to prevent odor transfer.

Prepare the topping:

• In a mixing bowl, use an electric mixer fitted with the whisk attachment to beat the cream, sugar, and vanilla on medium-high speed until medium-stiff peaks form.
• Garnish the chilled pie with whipped cream. Top with fresh lime zest or lime slices, cut into slices, and serve.
• The pie can be baked and chilled (without the topping) 1 day ahead. Once it’s cold, cover loosely with plastic wrap, then top within a couple of hours of serving. Any leftover pie will keep, covered with plastic, for several days in the refrigerator (the crust will soften over time).