Microwave Wisdom: Why Not to Microwave Eggs in Shells
You must break the eggs out of their shells before microwaving. Never microwave eggs in shells. If you cook an egg in shell in the microwave, it’s likely to explode. Microwaves heat so quickly that steam builds up faster than an egg can ‘exhale’ it through its pores and the steam bursts through the shell. For the same reason, when microwaving, always prick the yolk of an unbeaten egg with the tip of a knife or a wooden pick. The vent you create allows the steam to escape safely.
All models of microwave ovens tend to cook foods unevenly, leaving cold spots. To encourage more even cooking, cover the dish, stir the ingredients, if possible, and either use a turntable or rotate the dish at least once or twice during the cooking time.