Small amounts of sunflower seeds (or other seeds and nuts) can easily be roasted in the microwave, according to UNL Food. The process takes five minutes or less and requires a small amount of oil or butter, the seeds and a microwave.
Spread up to 1/2 cup of seeds in a single layer on a microwave-safe plate or bowl. Add 1 teaspoon of oil or butter per 1/2 cup of seeds. Microwave for two to four minutes, stopping after each minute to stir and check for browning. Roasting is complete when seeds are slightly browned and fragrant. Roasted seeds can be stored in an air-tight container in the refrigerator for one to two weeks or frozen for one to three months.