This is such an awesome subject that is helpful for post diet and foods for digestion after abdominal surgery.
I had robotic sigmoid colectomy and opened belly button down for diverticulitis.
No dietitian. Was told to go back to "regular diet" LOL Sounds scary.
I think you must focus first on what your body needs first to heal and maintain proper nutrition.

It is difficult to take that chance of what you can eat and not eat that you may or may not have "issues' with during the digestion process. You have to experiment and learn what your body reacts to.

I started with very small meals. I focused on getting all the nutrition your body needs and boy that is a lot to eat! Thus, vitamins and supplements are a must, and you have to think about the absorption.

exp. A banana, yogurt for breakfast. I would open capsules of zinc, probiotic or any other capsule to add nutrition and saving space in digestion process with a spoonful of fig jam. Coffee or tea with local honey and then other vitamins to help absorb. I also take multi vitamins.
I also would make scrambled eggs with olive oil, spinach bacon and whole grain bread. I would save my yogurt for later if I had eggs due to space! You must make choices of what you eat and when.

My cooking has not changed much. Since they cut out the damaged colon, I do not have that issue anymore.
Spices do not bother me. But, anything hot is a no!

I did try ice cream again. I learned that if it was just a small bowl it did not cause lactose issue. But, I had to learn that amount by eating too much! I do not drink milk but can have cheese. I wish I could get more calcium but, my body cannot absorb supplements (kidney stones) and have to get in foods.