I assume its three shakes plus the foods you have mentioned in your post?
You could try make a fairly basic ricotta bake adapting to the egg and ricotta cheese amounts you are able to have.
When I was on my pre-op diet which allowed only three shakes and low carb vegetables, a few times if I needed something different I would have cottage cheese or chicken in place of the shake but made sure it was to the same calorie count or protein amount as the shake. I would have the low carb veges with it. It wasn't the right thing to do, and I certainly don't want to encourage you to do it, but it did save my sanity and kept me on track for some of the time, unfortunately I wasn't the best pre-op person, thankfully I am much better at post op haha