I would have to agree with some comments that we try to eat as diversely as we can for the sake of both nutrition and enjoyment. However, we have simplified our diet in that I barely use cookbooks or make complicated dishes with strictly required ingredients. Eggs from our ducks, veggies and berries from the garden, homemade sourdough, some peanuts we buy raw and roast ourselves, etc. For meal prep I start by looking in the fridge and freezer: what needs to be eaten? What would go well together? Does the dish have an official name? Nah, but I can make one up.
We also tend to eat seasonally. In the summer we eat a lot of salads although that word is used loosely and might not contain lettuce. Stuff mixed and dressed, eaten cold or room temp, that's a salad. In the winter I make more soup but again, whatever veg fresh or frozen is available, some lentils, plenty of herbs. Cuddle with the bowl and listen to the wind outside. Delicious.
I do buy chocolate, cheese, hemp milk, raw cow's milk when our daughter's cow is giving it. Also olive oil and coconut oil, tea and coffee. And my husband would say "Don't forget the tortilla chips." A food group in itself for him.
For several years I have been experimenting with growing beans for drying and some kind of grain. Successes have been black beans and grain sorghum: for hot cereal, not syrup.