In every fire, there are several processes of heat transfers that occur: conduction, convection, and radiation. Conduction isn’t relevant to browning marshmallows, but convection and radiation are. As mentioned above, convective flow is the gases that rise off the visible flames. Due to their speed and movement, these are not ideal to brown a marshmallow. Instead, toasters should stay to the side of the flames and hover over the glowing coals to best caramelize the marshmallow. Patience is always the key to achieving a perfectly roasted (and not burnt) marshmallow.