Preheat oven to 375.

Peel, seed and chop the butternut squash into roughly 3/4 inch pieces. Place on a sheet tray with the whole, peeled garlic cloves and toss together with olive oil, salt and pepper. Spread everything out in a single layer.

Roast on the middle rack. After 20 minutes, add the thyme and turn squash and garlic so the other side browns. Cook for another 20-25 minutes. You want the squash to be very tender and just lightly brown.

Remove from oven and place squash and garlic in a bowl. Using a potato masher, mash the squash and garlic until it’s all mixed up and you can’t see any more chunks. If you like a very smooth texture, you could pulse it in a food processor instead. I like it more rustic so I just mashed mine in the bowl.

While it’s hot, add the mascarpone (or sour cream), butter and 2 tablespoons milk. Stir until smooth and creamy. If it’s still too thick, add more milk a little at a time until you like the consistency. Season with salt and pepper to taste.