shredded cheese (try cheddar, pepper jack, or Mexican blend)
Scrub potatoes well. Poke each potato with a fork 2 or 3 times. Microwave on high for 5 minutes, turn potatoes over, and microwave another 3 to 5 minutes, or until easily pierced with a fork. Set aside.
In a microwave safe bowl, combine beans, salsa and corn. Microwave for 2-3 minutes, stirring occasionally, until heated through.
Cut potatoes in half length-wise and flatten with a fork. Divide bean mixture between the four halves. Sprinkle with cheese and serve warm.