Prepare your pie crust according to your preferred recipe. Chill the dough for at least 2 hours.
In a large mixing bowl, combine cherries, sugar, cornstarch, lemon juice, vanilla extract, and almond extract. Mix thoroughly and refrigerate while preparing the crust.
Roll one chilled dough disc into a 12-inch circle and carefully place it into a 9-inch pie dish.
Using a slotted spoon, transfer the cherry mixture into the pie crust, reserving any accumulated juice.
Place the reserved juice into a small saucepan. Cook over low heat for 3–4 minutes until slightly reduced and thickened.
Allow the reduced juice to cool for 5 minutes, then pour it over the cherries. Gently combine.
Dot the filling with small cubes of butter.
Refrigerate the pie while rolling out the second dough disc into another 12-inch circle.
Cut the dough into strips and create a lattice crust over the filling.
Trim excess dough and crimp the edges.
Whisk together the egg and milk. Brush over the crust and sprinkle with coarse sugar if desired.
Refrigerate the assembled Homemade Cherry Pie With Thick Filling for 20–30 minutes.
Preheat oven to 400°F (204°C).
Place the pie on a baking sheet and bake for 20 minutes.
Reduce oven temperature to 375°F (190°C) and continue baking for 30–40 minutes until the crust is golden brown and the filling is bubbling.
Cool on a wire rack for at least 3–4 hours before slicing and serving.