1. Combine all the ingredients in a microwave-safe bowl (2 1/2 liter or 2 1/2 quart). Cook without covering the bowl on HIGH (1200W) for 2 minutes.

2. When it reaches a boil, reduce the power to 80% so that it will not boil over and continue cooking for 4 minutes or until mixture reduces itself by half.

3. Take out and strain through a medium mesh strainer into a different bowl, to prevent the sauce from continuing to cook from the residual heat. Discard any solids. The sauce will thicken as it cools.

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.