In a microwave save dish, place the squash. Cook on high for 3 to 4 minutes. Remove from the microwave and slice into two equals halves.
Remove the seeds and discard them. Sprinkle salt and pepper over the cut side of the squash.
In a medium bowl, mix together the cheddar, Havarti, seasoning, and half & half. Divide it equally between the two halves. Top with garlic clove and Parmesan cheese. (the clove of garlic will roast without having to roast it seperately.)
Cover with foil and bake for 25 minutes. Uncover and bake another 25 minutes or until bubbly and tender.
Remove from the oven, stir, garnish with green onions, and serve.