Guaranteed to rise and simple to make. You will need 2 clear identical glasses, a mixing bowl and a whisk (hand is fine and I have been known to use a fork!). These will take about 10 minutes so are great to do near the end of a roast.
Sometimes I add a pinch of something different to the mixture to alter the flavour. I have tried at various times, cumin, dried chopped chillies, curry powder, mixed dried herbs, thyme etc.