To smoke vegetables in an outdoor smoker, start by preheating your smoker to the desired temperature, typically around 200-250 degrees Fahrenheit. Meanwhile, prepare your vegetables by rinsing them and cutting them into even pieces. Some popular vegetables to smoke include bell peppers, zucchini, eggplant, and mushrooms.Next, season your vegetables with your choice of oil, herbs, spices, and salt. You can also marinate them in a mixture of oil and vinegar for added flavor.