We first started cooking our food to make it more easily digested and to enable it to be more shelf stable (cave stable?). Once we graduated from spit roasting to cooking our dinners in a metal or clay pot, we were able to prepare foodstuffs that were more liquid rather than just chunks of meat skewered and suspended over the fire. I’m sure the first chefs quickly learned that viscous solutions also have a tendency to stick to their container and caramelize unless their proximity to the fire was attended to regularly. So much time and energy has been spent on enabling us better control of our heat source through inventions of things like stoves and thermostats, why not take advantage of them? I always end up telling less experienced line cooks; “the burner doesn’t just go on and off, there’s a whole lot in the middle”.
A pot on the stove needs constant adjustment. Sometimes this can be accomplished by merely stirring it or setting it off center of the heat source. I typically offset a stock or reduction so that the bubbles rising on one side help to push the impurities over to the other more stagnant side giving me the chance to skim them away. Things change as they cook too. As soups and stews simmer away on a stove, they get thicker, thicker solutions hold more heat and will require you to routinely lower the temperature of your burner in order to maintain that lazy bubble you’re looking for.
Aggressive cooking techniques need aggressive heat. Grilling, roasting, sautéing, and other dry heat cooking methods are all about evaporating moisture and getting it out of the way to allow browning to take effect. Hence the sloped sides and large surface area of a sauté pan; its design allows water to escape quickly bettering the likelihood of you achieving the result of GBD (golden brown and delicious). An attentive cook will listen to the pan and turn it down when the sizzling and popping sounds go from aggressive and evenly paced to violent and turbocharged. Avoid using too much oil when cooking with gusto. It has a tendency to burn and spatter or even catch fire. Experiment with temperature next time you brown chicken breasts in a pan by changing the heat level applied to the pan for each breast, hotter each time. Take note of how they change in color and appearance as you progress in temperature.