For the yogurt topping: Set three layers of paper towels or cheesecloth in a colander set over a bowl. Place the yogurt in the colander on the towels. Cover the yogurt with another layer of paper towels and set in the refrigerator for at least 6 hours or overnight.
Remove the top layer of towels and scoop the strained yogurt into a mixing bowl. (The amount of yogurt will have diminished by about half.) Mix in the honey, the zest and half of the juice from the lemon.
For the pie: Preheat the oven to 325 degrees F. Toast the chopped walnuts for 5 to 10 minutes.
Whisk the honey, cream, brandy, vanilla, cinnamon, salt, 3 yolks and whole egg together. Slowly add in the butter while mixing. Turn the oven to 375 degrees F.
Bake the pie crust for 15 minutes, then remove from the oven and allow to cool slightly.
Return the oven to 325 degrees F. Brush the crust with an egg wash made of the remaining 1 yolk and 2 teaspoons of water. Fill the pie shell with the toasted chopped walnuts. Pour the custard mixture over the walnuts and fill to the rim of the pie shell. Decorate with the walnut halves, by placing them on top of the custard mixture.
Bake the pie until set, 35 to 45 minutes. The custard will be set if it only slightly quivers when jiggled. Let stand for 1 hour before serving. Refrigerate the pie and it will keep for 2 to 3 days. Warm slightly before serving and serve with a dollop of the yogurt topping.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.