This is how I cook. My wife (whom I love dearly) cannot tackle a meal without a cookbook, a shopping list, and a trip to Food Lion or Giant (or both, because Giant has better meat and produce while Food Lion has some things we can’t get anywhere else). I, OTOH, scan through what we have in the fridge and the pantry (and sometimes the freezer, especially for veggies), start throwing things into pans and pots, and produce a meal while my wife (who loves me dearly) looks at me like I’m conjuring dragons from thin air.
Downside: I can almost never reproduce the same meal twice. If I’m on a Destroy All Leftovers kick, I may not even know what actually went into the result.