To begin with, we will peel the onions, cut them in half and from there we will cut them into rings (as thin as possible). Also, we will grate the cheese. Both ingredients are going to be reserved for later.
In a large and deep container we are going to mix the water, the oil and the beer. In addition, we will add a little salt and gradually incorporate the flour. Although at first we can stir the mixture with a spoon, later we will knead the mixture on a clean work surface to obtain a firm and homogeneous dough.
We will put the dough on the oven tray spreading it on the base so that it is very thin -with the contour we will form an edge-. We will cover it with cream cheese and place all the onion slices on top. We will season to taste, we will sprinkle with the aromatic herbs (this is to the taste of each one but we can opt for oregano, thyme and/or rosemary), we will spread the grated cheese and water with a thread of extra virgin olive oil.
With the oven preheated to 200ºC with heat above and below, we are going to cook the coca in the lowest part of the oven for about 30-35 minutes (or until we see that the edges of the dough begin to look golden). We will immediately serve ready to enjoy this delicious delicacy.