I make quinoa as a side dish to most dinners. It cooks faster in a rice cooker and it’s arguably healthier (high nutrient richness, higher fiber, complete protein source- unlike most grains). Here is my favorite thing to do with leftover quinoa for the next morning.
Put leftover quinoa in a container and cover with non-dairy milk and a little maple syrup (or you can add different sweetener the next morning). Let stand in fridge overnight. The next morning, heat in microwave for one minute. Add sweetener and/or fresh fruit/nuts of your choice!