Toffee and caramels are simple but time-consuming confections to produce. The dairy products contained in both require constant stirring as they cook to prevent scorching. They have a tendency to foam in the early stages of cooking, requiring a low heat to prevent boiling over, and the best flavors and color are developed when they are cooked slowly, not quickly like hard candy. The time required to cook them while stirring constantly is the reason most operations that produce caramels have a fire mixer, which automatically stirs the batch as it cooks, reducing labor costs.