What works well for me is to make full recipes of different things and then freeze them in individual servings. Like chicken soup or a vegetarian stew.
I too am on a special diet, one that isn't like any i have encountered. Its just the NeilM diet. But it works for me and helps me sleep well and feel fine.
I have an Instant Pot which I couldn't live without. It not only pressure cooks but it slow cooks, sautes and is a rice cooker among other uses. Part of my evening meal is always (dried) beans and brown rice and for that alone, the Instant Pot is worth the expense.
While I cannot eat red meat, I can eat fish and chicken so I can easily fry a fish filet. Also I find that the Gardein Ultimate Burger and Dr. Praeger burger are both handy and fit my unique diet. Hopefully those are available where you are.
While I generally have the same things for breakfast and lunch, my suppers rotate thru chicken, vegetarian, fish, vegetarian, and I don't eat one without planning the next.
Hope this info helps. If you have questions, post them. I'm around fairly often.
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Your neurodiverse (Aspie) score: 120 of 200
Your neurotypical (non-autistic) score: 74 of 200
You are very likely neurodiverse (Aspie)
AQ = 38 MBTI = ISTJ Gender = Non-binary
I strive not to perseverate. You can PM me for more info.