1. Put corned beef into an ovenproof bowl. Cover with the edge-open wrap and microwave on 600W for 2 minutes

2. Loosen corned beef. Add miso sauce and pepper, mix until smooth. Fill in a serving dish.

3. Serve with some bread to spread on.

For how long you should cook with your microwave oven, see Cooking Time vs Wattage Conversion.
For more tips of using Microwave Oven, see Sachiko's Guideline to Microwave Cooking.