We often go over to my wife's sister E for a visit. Usually we will have a meal there as well. Being the helpful brother-in-law that I am, means that I will help with the prep and the cooking. They have a huge vegetable garden and the produce they have is amazing, things like potatoes, tomatoes, cucumbers, zucchinies and beans are constantly on their table throughout the season.

It's funny, whenever I go to someone elses kitchen, I always check out the equipment. E just has the usual run of the mill stuff that most kitchens would have, nothing as exotic as a truffle slicer (yep, I've got one) or even mundane like a mouli or a wire whisk. But still I can get by.

However E has one piece of equipment that I find hard to work with and that is her frypan. It's just a commercial variety made of stainless steel and not a particularly thick guage at that. Really, I'm not fussy about kitchenware and ordinarily would have no problem sauteing in her pan. It's just that the frypan is not flat, there is a hump in the midddle that causes the oil or fat to migrate to the edges of the pan. This convex pan is my bane. No matter what you do it's impossible to get an even, thin smear of fat all over the bottom, with the consequence that anything in the middle of the pan has a tendancy to stick.

Does this drive me mad? YES!

So about twelve months ago, we went out and bought E a new non stick frypan, a Tefal, you know the one with the red spot in the centre, that disappears when the pan is at the correct temperature for frying or whatever. The one Jamie Oliver is pushing. So it's a pretty reasonable frypan, we have one ourselves. So problem solved, or so I thought.

Over Easter we had Sunday lunch with E and family. Helping out in the kitchen, I needed to fry something. Grabbing the pan I put it on the glass stove top, the type that has an electric element underneath. I put some oil into the pan and all of it ran to the edges of the frypan. The hump was back! Now this was curious, as my wife says "Once is an accident, twice is on purpose."

At home we have a gas stove and all of our frypans are flat. Could it be something to do with an electric cook top? Flowing electicity has two properties - heat and magnetism - both of which have been harnessed to cook with. Could it be that magnetism was having some effect on the frypans? I rang the Essential Ingredient, who stock a wide range of cookware, to find out.

I spoke to a very helpful person, but they were unable to say whether or not my theory was correct. What they did say however, was that non stick frypans should not be subjected to a lot of heat. How much is a lot? She suggested omelettes or crepes were fine, but frying a steak was not. Apparently the non stick coating breaks down at higher temperatures, and eventually the pan jumps the shark and sadly food starts to stick.

The best frypan we have at home is twenty-five years old, weighs a ton and is made from cast iron. It is non stick, but in the old fashioned sense. It has been seasoned by having hot oil in it for a few hours and is never washed, only wiped clean. If the pan starts to stick, we simply repeat the seasoning and all is well again. If you look in any commercial kitchen, the most common frypans are made from black steel and would have been seasoned as described. Look at woks, they are made from steel and properly used and maintained, food never sticks.

There is always a place for a non stick pan in the kitchen, but if you want one to last, be careful and don't overheat it.