Infusing is a way to extract flavor from an ingredient with the help of a solvent, such as water, alcohol, or oil. Varying the temperature and type of the solvent causes different flavor molecules to be extracted from the cells of the ingredient, which in turn affects the taste and aroma of the solvent. The most common example is vanilla extract, which is made commercially by steeping the tiny vanilla beans in hot alcohol. Adding hot water to tea leaves and spices for chai is another way to infuse a liquid with flavor. To make rhubarb confit, oil is slowly infused with rhubarb, chiles, and garlic for hours in a low oven.