Thoroughly wash sweet potato and pat dry. Pierce skin all over with fork to create vents and place sweet potato on microwave-safe plate.
Microwave 1 medium sweet potato for 6 minutes on high, turning sweet potato over halfway through cook time. Note: if your potato isn't tender after 6 minutes, continue microwaving in 30-second increments, checking potato after each session.
Cut sweet potatoes open down center, like a hot dog bun. Season with salt and pepper to taste and top with butter, if desired.