I use butternut, acorn, and buttercup squashes to make these recipes. It's quick and easy and usually pretty tasty.
First, I cook up the squash, same way for any variety:
Cut in half with large knife. Scoop out seeds. Place in microwave-safe baking dish, with cover if possible. If you don't have a cover, use plastic wrap to cover the squash. Microwave for 6-10 minutes, depending on the size of the squash. You want the "meat" to be fork tender. I usually let it cool a bit, then scoop as much of the insides as possible into a large bowl. Then I add any (or all) of the following, depending on what I have in stock:
1/4 cup cream
1/4 cup sour cream
1 large egg
1/4 cup mayonnaise
Mix it all really well, with beaters or potato masher.
You can also add spices, such as garlic powder, onion powder, seasoned salt, adobo, sazon, whatever you like. If I don't use any of the seasonings, I'll top it with brown sugar. If I use seasonings, I top it with grated parmesan cheese.
After everything is mixed, I pour it into a casserole dish and bake at 350F for 25-30 minutes.