I haven't done these before personally but I always butter the indents when cooking anything like muffins and that makes them come out smoothly. It also will probably taste a bit nicer than spray oil, I find that can taste a bit strange sometimes if you use a lot.

If you're looking for something you can freeze and add to other meals, then I would recommend Yorkshire puddings. You can make a batch of them and freeze them, and they only take a couple minutes to heat up in the oven and go great with anything you serve with gravy. One thing I like to do is get a rotisserie chicken, pull some meat off, and heat up some roast potatoes or fries, a couple of yorkshire puddings, a side of frozen veg medley or some garlic butter broccoli and make up some chicken gravy usually with gravy granules. It's a simple meal but really tasty, and if you want you can add more to it to make it more substantial or scale it up to serve to other people. Some boxed or frozen homemade mac and cheese for example goes well (For some reason Kraft mac goes well with chicken gravy), you can make stuffing up, or more veg. But the basic one is easy to do, delicious and only needs you to put on the air fryer. If you want I can give you my secret recipe (which is my grandma's secret recipe, though it's pretty much the same as everyone else's)