To make Lemon Oil, combine 2 cups of vegetable oil with the shells of 4 lemons that have already been juiced and a few sprigs of fresh thyme in a heavy saucepan. Place the pan over medium-high heat and bring to a boil. Immediately lower the heat and barely simmer for 15 minutes. Remove from the heat and allow to cool. Strain into a clean container. Cover and store in a cool spot for up to 6 months. Use the oil for sauteing, frying, and for vinaigrettes.