Air fryers are sweeping the nation. But what is an air fryer? How does it work? And, most importantly, do you need one? Here’s the lowdown. Several years ago, a “miraculous” kitchen appliance appeared on the scene promising us that we could fry with air. A new treat for your health—up to 90 percent less fat! One manufacturer promised, “Healthy food for diet eating!” Imagine that—delicious, healthy fried food without a lot of calories. An air fryer is a small countertop convection oven designed to simulate deep-frying without submerging the food in oil. A fan circulates hot air at high speed, producing a browned and crispy fare similar to deep-frying but without the oil. Surprise! If you have a convection oven, you already have an air fryer. Air-frying is essentially convection baking under a trendy new name, with a convection oven being better for doing everything that an air fryer …