Make the crust dough: In a bowl, whisk the flours, salt, and sugar. Cut in the cold butter with a pastry cutter or your fingertips until you have pea-sized bits.
Sprinkle in ice water, 1 tablespoon at a time, tossing until the dough holds when pressed. Split into two discs, wrap, and chill for at least 45 minutes.
Prep the filling: In a large bowl, combine cherries, maple syrup, coconut sugar, arrowroot, lemon juice, vanilla, almond extract, and salt. Stir gently until the cherries are coated and the starch dissolves.
Let sit 10 minutes to begin releasing juices.
Heat the oven: Set a rack in the lower third and preheat to 400°F (200°C). Place a baking sheet in the oven to preheat as well. This helps the bottom crust crisp.
Roll the bottom crust: On a lightly floured surface, roll one dough disc into a 12-inch circle. Fit it into a 9-inch pie plate, letting the excess overhang.
Chill the lined plate while you roll the top.
Roll the top crust: Roll the second disc into an 11–12-inch circle. For a classic top, keep it whole and plan to cut slits. For a lattice, slice into 1-inch strips.
Assemble: Spoon the cherry filling (and all the juices) into the chilled bottom crust.
Dot with a few tiny butter bits if you like extra richness (optional). Top with the crust or weave the lattice. Trim excess and crimp edges.
Brush with milk and sprinkle lightly with coconut sugar.
Bake hot, then reduce: Place the pie on the preheated baking sheet. Bake 20 minutes at 400°F, then reduce heat to 350°F (175°C) and bake 30–35 minutes more, until the filling is bubbling in the center and the crust is deep golden. Look for steady bubbles to ensure the starch has activated.
Cool completely: Set the pie on a rack and cool at least 3 hours. This is key for clean slices. The filling will thicken as it cools.
Serve: Slice and enjoy as is, or add a spoonful of vanilla Greek yogurt for extra protein and tang.