Toast bun/muffin halves and spread with butter.
In a large microwave-safe mug sprayed with nonstick spray, microwave egg whites/substitute for 1 1/2 minutes.
Stir and microwave for 1 minute, or until set.
Or just scramble in a skillet sprayed with nonstick spray.
Top with chopped tomato or enjoy with tomato slices.
Serve with berries.