For the crust:
Combine flour, sugar, and salt in a medium bowl. Add cubed cold butter to the dry mix and coat the butter cubes with flour. Then use a pastry cutter, fork, or your fingers to work the butter into the flour mixture until it’s in pea-sized pieces.
Combine water, apple cider vinegar, and ice in a separate bowl. Add the liquid to the dry stuff a tablespoon at a time until the dough just comes together with some crumbs on the edges. You should need 4-6 tablespoons of the liquid.
Shape the dough into a round disc, adding more liquid in small drops if needed to get the dough to stick. Once the dough is in a solid disc, wrap it in plastic wrap and store it in the fridge for at least an hour, but overnight is best.
When ready to make pie, Preheat oven to 425 degrees F.
Roll pie crust out on a lightly floured surface until it’s roughly 10 inches in diameter. Transfer to your pie pan and trim edges to your liking. Poke some holes in the crust with a fork and line the pie with parchment paper or foil. Then add pie weights or dry beans to the crust.
Bake the crust for 15 minutes at 425 degrees F.
For the filling:
Heat honey and lavender in a small pot over low heat for 5-10 minutes. Add butter and let steep for a few minutes off the heat. Strain out lavender buds and add other filling ingredients. Whisk together well and let filling cool for a few hours in the fridge (or make in advance).
Pour filling into pre-baked pie crust. Bake at 350 degrees F. for 30-35 minutes until center is just set. Remove and let cool for 30 minutes. Then slice and serve.