You can make this recipe without any cream, but you have to substitute it with another type of liquid. Regular milk would be a good substitute. But you need to thicken it a bit by mixing it with cornstarch. 2 teaspoons of cornstarch would be enough for 1 cup milk. Another substitute could be coconut cream, which goes well with mushroom flavor. If you don't want to use any of these, simply add more pasta water and make sure to season the mushroom pasta sauce well. Keep in mind that your sauce will not be as creamy.