Preheat oven to 350°.

Slice squash in half, remove seeds and place on baking sheet.

Brush 2 tablespoon olive oil on both sides of the squash (1 tablespoon per half) and then place face down in the oven.

While squash is roasting, melt butter and last 2 tablespoon oil over medium-high in a large skillet.

Add onions to skillet, stirring occasionally. After 5 minutes, add mushrooms.

After approximately 10 minutes, the onions should start to caramelize. If they look like they're burning at all, add an extra tablespoon of oil.

Add kale to skillet and continue to stir everything together until onions turn a nice golden brown color.

After 45 minutes, remove squash from oven and allow 10 or so minutes for it to cool off.

Once slightly cooler, use a fork to remove "spaghetti" from squash and place in a skillet; add rosemary, salt and pepper and stir everything together.

Add parmesan cheese if you wish and enjoy!