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Some things are just too much trouble for one portion. I waste a lot of food. I cook for more than one, but then only eat for one. People tell me to freeze stuff, but most of the time I don't want to live on frozen food. I want to cook.
What is it that makes cooking one portion "too much trouble"? I lived alone for most of my adult life. Granted, I love to cook and I teach classes on cooking for one, so I have double motivation, but I've cooked many dinners for just myself with no leftovers. I've made single portions of (among other dishes) sherry braised chicken, beef stroganoff, quiche Lorraine (with homemade crust), braised short ribs, stuffed bell peppers, macaroni and cheese, chicken and dumplings, enchiladas, salmon and vegetables in parchment paper, risotto, pot pies, Thai curry, and any number of pasta dishes (usually with one portion of fresh made pasta). For side dishes, I've made single portions of rice; grits; mashed potatoes; roasted or steamed green beans, asparagus or broccoli; spinach, broccoli or potato gratins; all kinds of salads from potato salad to coleslaw to grain salads. Baking can be a bit tricker, but I often made 2 biscuits or a single serving of fruit crisp, and I came up with a successful recipe for enough pastry dough for a 4-inch pie tin. Sauces can also be difficult to make in very small quantities, but many of those are possible too -- Hollandaise or lemon curd (with one egg yolk) or bechamel with (3 ounces of milk).
In most of those cases, it's no more difficult to make one serving than four. In many cases, it's much easier. It does help to have the right cookware: for the sauces and grains, it's essential to have a very small saucepan. I have a .75-qt. copper saucepan that I use for sauces and 1-qt. saucier with a lid for rice and grits. If you want to braise small amounts of meat, a 2-qt. cast iron pot with a lid is nice.
It's true that there are a few dishes that aren't possible to make for one without having leftovers. Roasts fall into that category and whole roasted birds can too, unless you can find poussins or Cornish hens (although a Cornish hen is still two dinners for me, it's much more manageable than a regular chicken). Most other dishes can be made for one. That doesn't mean you won't have leftover raw ingredients -- if you make one serving of braised cabbage, you'll still have the rest of the cabbage in the fridge. In those cases, I plan on other meals within the next week or 10 days that use cabbage -- coleslaw, a stir fry dish, etc.
You've already said you don't like the casual approach suggested by some -- you want a "proper" dinner. You don't like cooking extra food and freezing. So what's left besides learning how to make small amounts of what you do like? What is it that's problematic about that for you? Is it that you don't know how to reduce recipes? You don't know how much to make? That takes practice, but it's pretty easy once you get the hang of it. (I've written articles on both those topics which, unfortunately, I can't repost here, but if you're interested, I can post links to them). If it's motivation, that's another problem entirely.