Preheat oven to 350℉.
Cut kabocha squash in half. Remove seeds and rub flesh with olive oil.
Place squash on a baking sheet and transfer to the preheated oven. Roast for about 30 minutes or until you can easily pierce the flesh of the squash. Set aside to cool.
Divide the crushed gingersnaps and granulated sugar into two bowls and mix well.
Pour half of the melted butter in each of the bowls and mix with a fork until it resembles wet sand.
Transfer the cookie mixture to two 9" pie pans. Press the cookie mixture into the pans. Transfer the pie pans to a sheet pan and bake in the preheated oven for 8-10 minutes.
Scoop the cooled squash flesh from the rind and measure out 15 oz and transfer to a large bowl.
Pour evaporated milk over the squash. Using and immersion blender, puree the ingredients until they're smooth.
Whisk together the ginger, cinnamon, sugar, and egg. Add the egg mixture to the squash mixture and whisk until smooth.
Preheat oven to 425℉.
Pour the filling in the two baked pie shells, dividing it evenly.
Bake the pies at 425℉ for 10 minutes. Reduce the temperature to 350℉ for another 20 minutes or until the filling is set and no longer jiggles. Remove from the oven. Transfer to a rack and cool completely.