New to this. I have some questions. An answer to any of them would mean I know more than I know now! What does the cornflour and vinegar do? Have read two different recipes, one says do not open the oven door after cooking, the other says open a little until completely cooled. Which is better? I am aiming for a chewy meringue if possible, and using candarel instead of sugar, if that makes a difference. TIA.