Combine flour and sea salt in a bowl, then work in the cold butter cubes using your fingertips until the mixture resembles coarse breadcrumbs—this creates those flaky layers we want in the crust. Add the ice water a little at a time, mixing gently until the dough just comes together without overworking it. Shape the dough into a disk, wrap it in plastic, and refrigerate for at least 30 minutes while you prepare the other components. I find that a properly chilled dough is much easier to roll out and less likely to shrink in the oven.

Preheat your oven to 400°F and pierce each sweet potato several times with a fork to allow steam to escape during roasting. Place them directly on the oven rack and roast for about 45 minutes until they're completely tender and easily pierced with a knife. Once done, remove them from the oven and let them cool enough to handle, then peel away the skin. The flesh should be soft enough to mash easily.

Reduce the oven temperature to 375°F. On a lightly floured surface, roll out the chilled dough from Step 1 to about 1/8-inch thickness and transfer it to a 9-inch pie pan, trimming any excess overhang. Prick the bottom and sides with a fork to prevent puffing during baking. Bake for 15 minutes until the crust is set and just beginning to lightly color. This partial bake ensures the crust won't be soggy from the filling.

While the crust bakes, add the roasted sweet potatoes from Step 2 to a food processor and blend until completely smooth. In a separate bowl, combine the softened butter with both sugars and cream, then add the room-temperature eggs one at a time, beating well after each addition. Pour this wet mixture into the processor with the sweet potatoes and add the bourbon, nutmeg, cinnamon, and sea salt. Process everything until the filling is silky and homogeneous—this takes about 1-2 minutes of processing. I prefer freshly ground nutmeg here because it adds a noticeably brighter, more complex spice note compared to pre-ground.

Remove the partially baked crust from the oven and reduce the temperature to 350°F. Pour the filling from Step 4 into the warm crust, spreading it evenly. Bake for 1 hour and 10 minutes until the filling is set around the edges but still has a very slight jiggle in the center when you gently shake the pan—this ensures the filling stays moist and custard-like rather than becoming rubbery. Let the pie cool completely at room temperature before slicing, at least 2-3 hours, which allows the filling to set properly and makes serving much cleaner.