To make dough, whisk together buckwheat and all-purpose flours. Cut in butter with a fork or pastry cutter. Add ice cold water and stir to create a rough dough. Add an extra tablespoon of water if it seems too dry. Form dough into two equal balls. Slightly flatten each one into a thick disc and cover in plastic wrap. Place in fridge to chill for one hour.
While dough is chilling, make pie filling. Add peeled and very thinly sliced apples to a large bowl with maple syrup, all-purpose flour and cinnamon. Stir to coat. Cover the bowl with plastic wrap and place in fridge while crust is being finished.
Once the dough has finished chilling, roll out one disk on a floured surface – about 1/8th inch thick and larger in area than the pie pan itself.
Place this sheet of dough into pie pan and use a sharp paring knife to trim off the excess.
Preheat oven to 400°F. Spoon apple mixture and all the juices from the bottom of the bowl into the pie crust. Roll out remaining portion of dough to decorate top of pie. You can weave a lattice, use cookie cutters to cut out fun shapes or simply trim and crimp another single sheet of dough on top, poked with a few steam holes.
Bake pie for 50 minutes, pausing after 35 minutes to cover crust with a pie shield or tin foil to prevent it from getting too dark. Once baked, remove from the oven and place on a wire rack to cool.
As soon as the pie is in the oven, start making the apple cider molasses.
Pour cider into a large pot and allow it to boil for 40 minutes, stirring occasionally.
Reduce heat to medium-high and continue to boil, stirring often for about 10-15 additional minutes. The liquid will start to foam, turn syrupy and be reduced to about 1 cup. Remove from heat and drizzle on top of the freshly baked pie. Serve and enjoy.