Peel and halve butternut squash. Scoop out seeds and cut squash into chunks. Add to a large pot and fill with enough water to cover by 2 inches.
Place pot over high heat, cover, and bring to a boil. Once boiling, cook squash for about 15 minutes, until tender and easily pierced with a fork.
While the squash is cooking, combine butter and cream in a small saucepan. Melt over low heat and whisk to combine. Keep warm.
Drain squash and return to the same pot. Mash with a potato masher, fork, or push through a ricer. Mix in the melted butter and cream, stirring well and mashing more to desired texture.
Season with salt, black pepper, and chopped fresh herbs to taste.
Notes
For a sweet side dish, reduce the salt and omit pepper and herbs. Mix in 2 tablespoons brown sugar and a pinch of cinnamon.