This is sort of a quintessential butternut squash soup, but I've made it with acorn squash and even a giant pumpkin once. You know. Anything squashy will do. Guys, it's easy. Here's what you need to do.
Cut up the squashy into cubes and put them on a big tray. Spread olive oil around and get some salt on there too. Put them in the oven at 400 or so.
Take a bulb of garlic and hack off the top so that all the cloves are just a bit exposed. Put that in the oven too.
Wait a while. I have no idea how long but you can just try eating a cube after a while. It's done when it's delicious. Maybe 30 minutes?
Peel those little garlic sections. Chop them coarsely.
Fry up some onions at the bottom of a big soup pot. Add some salt. Let them start to burn a little bit and then dramatically pour in a cup of broth and some dry white wine. I usually buy my broth. (you could have boiled down some veggies or chicken necks if you started an hour or two earlier!)
Add a stalk or two of chopped up celery, and maybe a pepper. Or any other vegetable of similar stature. How about a bunch of sage too? I like to add a couple hot little thai chillies with seeds removed.
Keep it simmering away and add more broth and quite a bit of wine. By the time I'm done I've usually used a whole tetra of broth, and at least a third of a bottle of wine. At some point add the squash chunks and garlics too.
Put a bit at a time into your blender and puree. Don't do too much at once or steam will explode out the top and you'll burn. Once it's all blended, transfer it back to the pot and keep simmering.
Taste it. Does it need more salt? add some. Pepper? probably. You're done!