Crêpes with a sweet or savoury filling are authentically Parisian. This version is filled with ham and fried mushrooms and finished with a crispy cheese collar.
1. In a large bowl, mix the flour and salt. In a separate bowl, whisk the rest of the ingredients together, then add to the flour mixture. Mix with a balloon whisk or electric hand whisk until smooth. Cover and leave to stand for at least 30 minutes.