Aromatics are typically the first step in many recipes because heating them in fat releases their volatile compounds, infusing the oil and the entire dish with their flavor. This creates a flavorful base upon which the other ingredients can build.
Aromatics, such as onions, garlic, ginger, and herbs, contain flavorful compounds that are often locked within their cell walls. Heating these aromatics in fat, like oil or butter, helps to break down these cell walls and release the volatile compounds responsible for their distinctive smells and tastes. This process, known as blooming, allows the fat to absorb these flavors, creating a flavorful foundation for the rest of the dish. Starting with aromatics ensures that their flavors permeate the entire dish, rather than being added as an afterthought. The heat also softens the aromatics, improving their texture and making them easier to incorporate into the other ingredients. Different aromatics release their flavors at different temperatures, so the order in which they are added can also impact the final flavor profile. For example, garlic can burn easily, so it's often added after onions have softened.
Don't overcrowd the pan when sautéing aromatics. Overcrowding lowers the temperature of the pan, causing the aromatics to steam instead of sauté, which prevents proper browning and flavor development. Cook in batches if necessary to ensure even cooking and optimal flavor release.