Microgreens are big on nutrition and flavor, and can be expensive to purchase. You can easily grow your own if you have a sunny area in your home, a shallow container, some potting mix, and microgreens seeds.
This article from Master Garden Debra Stinton Othitis of Colorado Master Gardeners provides everything you need to know for planting and growing microgreens.
Gardeners Supply Company has similar information that also includes great instructional photos.