I don't know where I got this recipe. I made it for the first time for Thanksgiving 2006. In 2006 I rarely wrote down which websites I found recipes on. I did a search online but didn't find anything close to this particular recipe.
This time I wound up, unintentionally, making huge batch. Squash was on sale and I bought the biggest most gigantic monster squash on the planet. I usually bake it in a 2 quart dish, but then I re-read the part where the thickness of the gratin should only be about an inch thick. I decided the 9x13 pan, that holds 3 quarts, would work better. The dish didn't seem to taste any different being thinner, but if you like crusty browned cheese, make the dish on the thin side.
If you look closely you can see little leaves on top of the gratin. These were the last surviving bits from my sage plant. I had to scrounge up these bits because most had succumbed to the cold weather. Good thing I made this dish when I did because it's brr freezing cold now and all the leaves are kaput.
Spaghetti Squash Gratin
1- 2 1/2 lb spaghetti squash
9 fresh sage leaves, 6 leaves finely chopped
1 garlic clove, minced into a paste
2 1/2 c Gruyere cheese, about 8 oz
3/4 c heavy cream
salt and pepper to taste
Chop your squash in half. Scoop out the seeds 'n' guts and throw them away. Place 1 half of the squash cut side down on microwave safe dish with 1/2 c water. Cover with plastic wrap. Nuke for 8-10 minutes. Repeat with remaining half of squash. (You could bake the squash in the oven for 45 min at 350. I'm a microwave girl so I use it when I can to save time.) Once squash is cool enough to touch, scrape out noodle like flesh with a fork. Place in a large bowl. (My squash had a lot of liquid so I let hang out in a strainer in the sink for a while.)
Preheat oven to 375. rub baking dish with butter. Toss squash with sage, garlic, 2 c cheese, cream, salt and pepper. Spread the mixture evenly in a baking dish. The mixture should only be about an inch or so thick. Sprinkle remaining cheese over top. arrange 3 sage leaves on top. bake 45 min. top with black pepper.