What is your favorite aromatherapy oil?

My favorite is peppermint. I use it when I get sick. It's like a cough drop it feels so good in your throat and chest. But I also keep a first aid kit of oils in my purse. Birch, cypress, tea tree, lavender, helachrisum, peppermint, black pepper and lemon. My midwife whom I get my oils from also wrote a book. Aromatherapy Speaking to the seasons of women's lives. By Lily Zerkle. You can also buy it on amazon. Good luck!