In a small skillet or omelet pan saute the sausage until it is browned

Remove the sausage with a slotted spoon and discard the drippings

Cut into bite-sized pieces and set aside

Melt the butter in the skillet and add the onion and mushrooms

Saute until the onions are translucent and the mushrooms have given up some of their juice

While the onions and mushrooms are cooking, beat the eggs until they are smooth and frothy

Stir in the milk, salt and pepper.