In a large bowl, mix together the flour, sugar and salt. Using a box grater, grate the cold butter atop the flour mixture. Working quickly, and using your hands, break the butter bits into the flour until they're evenly distributed and resemble the size of small peas. Add 1/4 cup of water and mix. The mixture will be shaggy at the point. From here, add 1 tablespoon of water at a time until the dough comes together. I ended up adding about 1 1/2 more tablespoons of water, equalling 1/4 cup water, plus 1 1/2 tablespoons. Flour your counter and dump the dough onto it. Knead the dough a few times until it comes together; form the dough into one solid disc. Wrap the disc with plastic wrap and transfer it to the refrigerator to chill for 1 hour or overnight.
Remove the disc of dough from the refrigerator. Liberally flour your work surface and rolling pin. Begin to roll the dough, being sure to rotate it every so often to avoid sticking, to a 12 to 14-inch round. Wrap the dough around the rolling pin and unroll it over the pie tin. Gently fit the dough into the bottom and up the sides of the pie tin. Trim the dough around the pie tin, and using your thumb and forefinger, crimp the rim of the crust into a v-shape. Score the bottom of the pie crust with the tines of a fork. Preheat the oven to 400 degrees F. Transfer the pie crust to the refrigerator to chill for 30 minutes. Line the pie crust with foil or parchment paper and fill it with beans, rice, pennies or metal pie weights. Transfer to the oven and bake for 15 minutes. Carefully remove the lining and pie weights and bake for an additional 5 minutes. Remove from the oven and allow to cool on a wire rack until room temperature.
Meanwhile, let's make the filling. Combine the buttermilk and chamomile. Allow the mixture to steep at room temperature for 2 hours. Give it a taste and make sure you can taste the chamomile. If not, it might need 30 more minutes. Pour the mixture through a fine sieve (if the holes are too big you'll have little bits of tea) to strain. Set aside.
Preheat the oven to 325 degrees F. In a medium bowl, whisk together the sugar, honey, flour, lemon zest and salt. Next, beat in one egg at a time, until the mixture is thick and thoroughly combined. Pour in the buttermilk and whisk until completely combined. Pour the buttermilk mixture into the par-baked pie crust. Carefully transfer the pie to the preheated oven and bake for 30-40 minutes, until the center of the pie is set. Allow the pie to cool on a wire rack until room temperature, about 1-2 hours.