Preheat the oven to 350.
Rinse 1 medium or 2 small Futsu squash. Cut in half from top to bottom, following the ridges in the squash. Scoop out the seeds and pulp. Use a large knife to carefully cut the squash into wedge-shaped segments following the shape of the squash.
Make a glaze with 1/2 C. tamari, 2 T. sesame oil, and 1/2 t. black pepper. If you like, add 1/2 t. ginger powder and/or 1/2 t. garlic powder.
Brush the cut sides of each squash wedge with the glaze.
Place the wedges with one cut edge down on the baking sheet. Roast for 15 minutes or until the bottom side is nicely browned, then remove from the oven and carefully turn the slices over to the other cut side. Bake for another 10 minutes or until the second side browns.