Preheat oven to 400°F (200°C).

Cut butternut squash into 2-inch thick slices crosswise.

Peel and remove seeds from each squash slice.

Cut the squash into 1-inch cubes.

Cut the red pepper into 1-inch squares.

Mince the garlic cloves.

Chop the parsley and fresh sage.

In a large bowl, combine the cubed squash, red pepper squares, olive oil, minced garlic, chopped parsley, chopped fresh sage, and fresh ground black pepper.

Transfer the mixture to a 2 1/2 quart gratin dish or shallow baking dish.

Sprinkle grated Parmesan cheese evenly over the top.

Bake for 1 hour, or until the top is golden brown and the squash is tender.