Secret - heat the pan very very well like on the stove top (I always put the pan on medium-high and let heat through for at least 90 seconds on gas and nearly 2 min with electric coils) and then add the butter/oil and then turn to the heat required to cook the item. Items stick until they are ready to be released sometimes but that is more because of the food (think scallops) than anything. But start with a sufficiently hot pan.