I have often considered writing a cookbook entitled "101 Things to Do with a Steamer." But there is really only one: to cook a lot of vegetables, preferably at the same time.
Most vegetables require only 5 minutes to steam. Exceptions include potatoes (10-15 minutes) and perhaps Brussels sprouts. Even veggies that are better sautéed or boiled (like cauliflower, mushrooms, onions) go well thrown into a steamer. And if you use a really big pot, you can steam enough vegetables to feed the whole family, or if it's just you and your significant other, have dinner for the week.
One of my favorite concoctions includes Brussels sprouts, cauliflower, white onion, tomato, and several red potatoes. After steaming the potatoes for 10 minutes, throw in the other vegetables. Include kale or broccoli for the green effect, if you have it.
Then, mix in a can or two of beans of multi colors. Recently I used a mix of fava beans and white beans. Add olives and nutritional yeast for flavor, and top with avocado.
Other vegetables that marry nicely include green beans, eggplant, broccoli, asparagus, and mushroom. Just slice, dice, and throw it all together. In the days that follow, heat the leftovers in a saucepan, but be careful not to overcook. Every extra minute on the stove is one less milligram of nutrition.