First, always consider that the tool you’re most likely to get the most use out of is the tool you have the most reason to use. Buy a pan to suit the type of cooking you like to do.
A big flat skillet will let you cook big batches of pancakes or grilled sandwiches.
A small frying pan will be your breakfast companion for years to come.
A generous dutch oven will serve you well for chilis, deep frying and crunchy sourdough breads.
So, the simple answer here is buy the pan you need first and build out a collection from there.
But, you ask, what would the Cast Iron Guy recommend?
You’ve read all about this cast iron movement and you’re looking at your chipped and scratched collection of aluminum pans from the supermarket and pondering leaping into building a legacy collection of cookware and begin replacing your nonstick throwaways.
You can’t go wrong with a medium-sized frying pan, of course. A simple ten to twelve inch pan is a staple of any collection and will be of great use in any kitchen.
But the piece I recommend, the piece that sits atop my stove and rarely ever finds it’s way back into the cupboard, the piece that I would buy as a gift for a friend or family member who was debating their first acquisition is a round griddle.
I own the Lodge 10.5 inch round griddle. *not a paid endorsment
This piece is a low walled, simple round, smooth pan with a bit of a lip around the rim. It’s simple to use and maintain, and cooks just about everything day-to-day: grilled cheese sandwiches, quesadillas, fried eggs, crepes & pancakes, and naan bread. It heats fast for warming leftovers. It packs well and I often take it local travelling to hotels (like when we go skiing in the mountians where we often have a kitchen but usually not-so-great pans.) It’s an all-in-one workhorse for egg sandwiches, grilling sausages, and my lunchtime meals-for-one. It goes into the oven as a roasting pan for numerous meat and vegetable dishes, and if I need to broil anything it’s the pan I turn to first.
And if I was rich, I’d buy these by the caselot and hand them out as gifts.
So, my recommendation: you need a great first pan, and you are not looking to fill a specific cooking need, I don’t think you can go too wrong with a simple round griddle.