Heat oil in a 1.7L saucepan over medium heat. To test if the oil is ready, touch the tip of a wooden chopstick to the bottom of the saucepan. If bubbles rise around the chopstick, then the oil is hot enough. Add the sliced shallots and gently stir so that they are evenly distributed and covered by the oil. Stir occasionally to ensure the shallots cook evenly, and allow to cook for about 15-20 minutes. Once the shallots brown, pour them into a mesh strainer over a receptacle, such as a pyrex glass measuring cup. After the oil has drained, transfer the shallots to a paper towel-lined plate to absorb any residual oil. The shallots will keep for a few weeks in an airtight container. Reserve the infused oil for cooking other dishes.