How long does it take to cook pumpkin soup with cream?

The thing that messes up squash soup the most is trying to cook it on high heat thinking it'll be faster - you end up burning the bottom of the pan and the squash turns into a shapeless paste. Medium-low heat is your friend here.

With me it goes like this: I cut the squash into medium cubes (around 3-4 cm), throw it in a pot with water and salt, let it boil and count about 25 minutes until it pierces easily with a fork. once it's really soft, I turn off the heat and blend everything in the blender (or use that hand mixer). then I add the cream, a bit of vegetable broth if I have it, black pepper, all that stuff already with the heat off so the cream doesn't curdle.

The total time you're looking at in the pot ends up being more like 20-25 minutes if the pieces are really uniform - the smaller and thinner you cut them, the less time you need. but honestly, if you're in a rush, it's better to cut everything into tiny pieces than to turn up the heat, because high heat makes the texture weird, like too watery or too dry. and just add the cream at the end, after you turn it off, that makes all the difference in the flavor.