This is one of those recipes that I like to push the flavors just a bit. The sumac lends a slightly brighter taste to the acorn squash while the parsley/tahini sauce brings the balance. It's a perfect partnership that also happens to be vegan (thanks for creamy white beans).
This soups is a bit more on the luxurious side with help from the creamy white beans and the parsley sauce. And yet, outside of the sumac, it's mostly pantry ingredients. I love having sumac on hand for making homemade za'atar mix.
Squash/Sweet Potatoes: I love the slight sweet/earthy flavor the acorn squash lends to the overall soup profile. However, you could use any type of winter squash soup or even sweet potatoes.
Spices: Sumac is such a lovely spice that I can't recommend enough that you pick up a small bit. However, if you want to leave it out and still proceed- I'd recommend replacing it with a bit of coriander.
Beans: Not a fan of beans in your soup? Ditch the beans and add a swirl of heavy cream or half and half.
Creamy squash is the perfect winter treat. Makes you feel full without loading up on cream and meat. This soup looks delightful.