- Make the crust: Using a food processor, pulse nuts with ½ cup flour until small crumbles form and the mixture resembles coarse beach sand. Add remaining flour, sugar, and salt and pulse to combine. Add butter and pulse until pea-size pieces form.
- In a small bowl, whisk together egg yolk, vanilla, and ice water. Slowly drizzle egg mixture into flour mixture while pulsing. Stop as soon as dough mostly comes together. Turn dough onto parchment paper or silicone baking mat then press dough together to make a round. Lay another piece of parchment paper or silicone baking mat over round and press to flatten. Using a rolling pin, roll dough out to a round about ¼-inch thick and 10 to 11 inches wide. Transfer to a 9-inch pie tin. Trim excess overhang to about 1 inch, and roll edges under to make a smooth and even edge, crimping as desired. Wrap in plastic and freeze for at least 2 hours, preferably overnight (for a flakier crust).
- Preheat oven to 350 degrees. Line pie crust with parchment paper and fill with pie weights or uncooked rice. Bake for 20 minutes, remove pie weights and parchment paper, then bake for another 10 minutes until center is firm and crust is evenly golden brown but not dark. Remove from oven and set aside.
- Make the filling: In a large bowl, whisk sugar, flour, and salt to combine. Set aside. In a separate medium bowl, vigorously whisk eggs, buttermilk, yogurt, and melted butter until smooth and well combined.
- While whisking, slowly add buttermilk mixture to sugar mixture. Whisk until there are no clumps and mixture is well combined. Add lemon zest and juice and vanilla, and whisk to combine.
- Preheat oven to 350 degrees. Place blind-baked pie crust on a sheet tray. Add cranberries to pie crust in an even layer. Slowly pour buttermilk filling over cranberries, filling to base of crimped edge. Give pie shake to ensure buttermilk mixture fills between cranberries.
- Bake in a 350-degree oven for 25 minutes, keeping an eye on the edges—if they’re getting too dark, cover them with foil. Rotate pie and bake for another 20 to 25 minutes, or until edges are set and center has a little jiggle. Remove pie and cool on wire rack. Serve with whipped cream.