Preheat oven to 350°, prepare a baking dish by coating lightly with olive oil. (I used a 8.5x8.5" square baking dish)
Peel the butternut squash, and slice in half lengthwise. Scoop out seeds, and cut into 1/2" thick slices. Arrange squash in the baking dish in an overlapping fashion
In a medium skillet over medium-high heat saute shallot and garlic for 4 minutes
Combine breadcrumbs, parmesan, and rosemary in a small bowl. Spoon 3 tbsp of shallot butter mixture into breadcrumb mixture and stir until well combined
Pour shallot garlic butter over butternut squash, lifting squash slices to coat all squash with mixture. Season squash with salt and pepper
Coat butternut squash with breadcrumb mixture
Bake uncovered for 55 minutes or until squash is tender and breadcrumbs are browned and crisp
Serve immediately with a sprinkle of additional fresh rosemary on top
Notes
If squash softens before breadcrumbs crisp increase temperature for 5 minutes until you achieve a browned crispy top
In a pinch substitute finely chopped onion for the shallot