Electric roaster ovens work well for cooking a meal for a large group, especially when your conventional oven is occupied. Unfortunately roaster ovens are a bit temperamental and can burn foods if left untended. The key to using roaster ovens successfully is monitoring them frequently and making adjustments in temperature and moisture levels, if necessary. Plain vegetables are fairly simple to cook, needing only adequate moisture to prevent burning. Sauced vegetables are a bit more tricky, because the sugar or fat in sauces can burn.
Spray the roasting pan with a small amount of cooking spray. Cooking spray simplifies clean-up and prevents burning when cooking plain vegetables, such as cooked peas, beans, carrots or roasted potatoes, as well as sauced vegetables, such as green bean casserole, baked beans or creamed corn.
For plain vegetables, fill the roaster insert with enough water to cover the bottom with 1 inch of liquid. Pour the vegetables into the roaster oven. For vegetables in a sauce, omit the water and simply pour the vegetables in the pan.
Cook vegetables at 300 degrees F. for 30 minutes to 1 hour, or until they are hot. Stir them every 10 minutes, and reduce the heat if the vegetables start to burn. The vegetables are done when they are browned and pierce easily with a fork.
Remove the vegetables from the roaster oven, and season to taste.
Add water as needed to keep the vegetables moist. Never pour water or food directly into the roaster oven, but use the large insert or place food in the small buffet pans if your roaster oven has that option.
Taste the vegetables frequently and turn down the heat when they are warm and tender. Overcooking can turn vegetables to mush.