I know exactly what you are saying, I am day 12 from surgery and actually had a tiny bit mash potato watered down with gravy yesterday and it was lovely. I know I shouldnt have but I did thin it right down lol.
You will be able to have them in a few weeks as you progress and you could use Unjury Cheese Sauce with them and if I'm correct it has 20g of protein in each serving. Check with your Nutritionist about this to make sure I am correct. I'm in Illinois and I was allowed this after Gastric Bypass.