Meals fall into 4 tiers for me:
Tier 1 - Survive - meals are things I can grab and eat from my bed. They are shelf stable. They an be prepackaged (chips, granola bars, trail mix, fruit pouches, etc) or they can be prepared (peanut butter and honey sandwiches, wraps, etc). The key is that when I need to eat, I don't have to get up from my bed at all to get them.
Tier 2 - Get By - meals take 5 minutes or less of standing to make. So these are things I can pull out of the fridge and eat right away or things I can make in the microwave so frozen meals, chicken nuggets, torilla pizzas, chickpeas, tacos, eggs, baked potatoes, etc.
Tier 3 - Alright - meals normal "weeknight" dinners - take 20-30 minutes or less to make, ideally use one pan or pot, no following a recipe or special ingredients, and don't have a lot of leftovers to juggle. Examples are pasta, curry, soup beans, quiche, etc.
Tier 4 - Thrive - meals are ones that take longer than 30 minutes, use ingredients I don't normally use, require following a recipe or video, or are otherwise energy intensive in some way.
Why divide meals up like this? Because I like to have options for each on my reusable grocery list so that I always have something that works for each around. With CFS, my energy and needs vary WIDELY from day today. I might prep for a week thinking it'll be a bed week but then I get some more energy and want to make a 3 or a 4 meal for morale. By having options for each, I'm covered.
Meal planning has never worked for me. What Sunday me thought sounded good later in the week was never what Thursday me felt enthused about cooking. I had found the concept of a capsule wardrobe very helpful and one day I realized I could extend the basic principle to my pantry. By settling on some core options in each category that I always had on hand, I didn't have to plan individual meals. I could just make whatever sounded good that night with what I had on hand.
Fiber, protein, and fat are the macronutrients that help with hunger so with any meal I put together I try to get all three.
Base is the bulk of a meal. Usually what I use for carbs and fiber. Examples include bread, torillas, (sweet) potatoes, high fiber pasta, rice noodles, any type of rice, veggies.
Protein is pretty self explanatory. Could be eggs, tofu, beans, tempeh, frozen fish, canned chicken or tuna. I prefer easy stuff that stays good for a long time.
Flare is anything that mixes up or elevates a dish. Examples are curry spice, bacon, sauce or condiment, cheese, etc.
It's important that each item can go with at most of the other items in other categories, even if the resulting meals are a little off beat.
By having at least 3 in each category, I could throw together a lot of different meals on the fly. Make that 4 or 5 in each category and the options are expand. If memory or executive functioning is an issue, printing out a list of some combinations you like ahead of time can help.
When I was first trying to figure out how to grcoery shop for myself, I ran across these reuseable grocery lists and felt inspired. While none were quite right for me, it wasn't too hard to make standardized grocery list and put it in a sheet protector.
The major pro of this way of doing grocery lists is that I never remember to write down things we need as I realize we need them. But with a reusable list - it's basicaly a list of things to check around my kitchen to see if we need something. I found it easier to just use a list of items to check in my kitchen to see whether we needed it before I went to the store or placed an order than to see I needed something while I was the middle of cooking and figure out when to write it down in between all the cooking tasks I was already trying to keep in my head. So just having a list of what to check worked way better.
I still had room to jot down things beyond the usual on it for when I wanted to try out a new meal or get something I only picked up rarely/annually - but those were items I was much more likely to remember to write down anyways.
So I highly recommend giving them a go!