For the coca (Spanish sheet cake), mix the yeast with a pinch of sugar in a little lukewarm water. Sift the flour and salt on the work surface, make a well and add the yeast. After about 15 minutes, add olive oil, beer and water and knead into an elastic dough.
Cover and let rise in a warm place until doubled in volume. Roll out the dough and place it on an oil-lined baking tray, cover it as desired (see variations below) and bake the coca (Spanish sheet cake) in the preheated oven at 200°C for about 25-30 minutes.