Heat oven to 400°F.
Line a baking sheet with parchment paper and set aside.
Cut, seed and slice your acorn squash into 1 inch thick slices that are 2-4 inches long. See video in the post above if you are looking for a visual.
Melt butter in a large glass measuring cup. Stir in the maple syrup and cinnamon until smooth.
Toss the acorn squash slices in the butter mixture, shaking excess off and arranging on the baking sheet. There should be maple butter leftover.
Bake the acorn squash for 15 minutes.
Remove from the oven, flip the slices, and brush with reserved butter (melt it in the microwave if it has solidified).
Return to the oven for another 5-10 minutes, until soft and slightly caramelized.
Sprinkle with sea salt and enjoy!