Welcome to I Swear by This, an interview series where we chat with our favorite fashion and beauty insiders about the beauty products they use down to the last drop. This week, we asked Jessica Matlin, longtime beauty editor, co-host of the Fat Mascara podcast, and most recently named the director of beauty at Moda Operandi, to share all the products she’s loving right now. If there was a beauty editor hall of fame, Jessica Matlin would have earned her spot years ago. There are few people with her knowledge, experience, and intuition in the industry. So it came as no surprise when Matlin was appointed director of beauty at…