The perfect bottom of a pot is made of either stainless steel or enameled steel. In its cold state, it has a slightly concave underside and fits onto the cooking zone just perfectly, regardless of whether it is round or square. Flexible induction cooking zones, on the other hand, automatically detect the size and position of the cookware and heat it up at exactly this position.
Make sure your pot has the right bottom thickness. For enameled steel, it should be 2–3 mm, for stainless steel pots with a sandwich bottom, the recommended thickness is 4–6 mm.
In its cold state, the bottom of the pot should be slightly concave, which means curved upward. Once it gets hot, it will expand and then lie flat on the cooktop panel. Nevertheless, the curve shouldn’t be too severe because then there will be too much of a gap between the cooktop panel and the bottom of the pot.
If the bottom of the pot is convex, or curved outward, it won’t lie flat. Valuable heat energy will then escape along the sides, and the food won’t be cooked evenly.
If the diameter of the bottom of the pot exceeds that of the cooking zone, your food won’t be heated up sufficiently and will therefore take longer to cook.
The diameter of the pot shouldn’t be smaller than the distance across the cooking zone; otherwise the heat energy will escape unused.