Do you often see recipes that have ingredients in them that you can't eat and just roll right past them? Something you may look at and think looks delicious and you would have loved to eaten that "before". All you need to know are a few tricks, a go to list and toss out the fear.
First let me say that there is probably already an adaptation to the recipe you are interested in somewhere on the internet. There are also tons of resources on blogs dedicated to food without that ingredient you can't eat. No gluten, dairy, soy, eggs, grains, tree nuts, peanuts, seafood or meat. Plus you can find blogs on living Night Shade Free, on a Candida Diet and the list goes on. So when the first stumbling block comes, go online and research.
Next, know what ingredients you can have and what they swap out for. I'm sure those specific blogs will have lists for you. When you are just starting off find and make your list, post on the refrigerator or wherever you plan meals.
Now, play with your food. Take one of those recipes that looks so good but has ingredients that you can't have, and substitute it with an ingredient you can have. Give it a try. You will never know how that substitute will hold up unless you give it a try.
As you give these substitutes a try, make notes. Make a note on the recipe, on your list, anywhere that you need to so when you give it a try the next time you have learned more about the cooking properties of that ingredient.
Lastly, please have fun in the kitchen. Don't be scared it will taste awful. Sometimes it will but more often than not, you will have found a new way to make the foods you like and can eat. If it is so bad that you just can't eat it go to plan B, eat out. :-)
As I shared with the world, I'm working on changing my health and my body over the next year. One way I am working on this is by journaling everything I eat. This means writing down what I ate and how much. I also keep track of how I feel physically. 
When I was making the Curried Macaroni and Cheese, I also made this Truffle Macaroni and Cheese just in case the first one didn't work out. Well both turned out great so we nibbled on both. Let me say they make great leftovers. Just make sure to heat thoroughly. However the Curried Mac & Cheese did not freeze then reheat well over time.
As I was wandering the market for mushrooms, they really didn't have many to choose from that day so I choose cremini and oyster. I was hoping to find some shitake but the two I used worked great. Now if they only had some truffles, then I would have been in hog heaven.