My domestic partner and I share the cooking responsibilities. When he first moved in with me six years ago, he suggested that we each "do our own thing" for breakfast and lunch, and only eat meals together for the evening meal. As a retired home economist, that sort of shocked me. I definitely was of the mind that shared meals was an important part of achieving a good relationship. But I went along with it. And it has proved to be wonderful!
We are both retired and had been before we got together. As it turns out, he gets up at 3 or 4 AM almost every day. Occasionally, I get up then, eat breakfast, and go back to bed. But about half the time he is eating an early lunch by the time I'm up and ready to make breakfast! There are also a lot of foods he won't eat, so if I want Mexican or Thai food, I just make it for myself at lunch.
For dinner, we take turns cooking, though on nights he cooks the main dish, if I want a salad or a vegetable cooked from fresh produce rather than frozen or canned (other than potatoes or sweet potatoes), I have to make it myself. He'll usually eat it, but he just isn't into fussing with cleaning and preparing most produce. But he's a good cook, making wonderful soups, stews, and various slow cooker meals, as well as roast turkey or chicken. When we cook, we typically make enough for two nights, so we each only have to "really cook" every four days. And when we make things like chili or soups that freeze well, we make enough to freeze, as well.
We do most of the grocery shopping together. He typically picks out the meats and I choose the produce.