Preheat oven and a cast iron frying pan (at least 10" in diameter if making two smaller pizzas, and at least 12" if making one large pizza) in a 500°F oven, on the lowest rack. The lower rack should be at the lowest level, and the upper rack should be about 6 inches away from the broiler element.

In the meantime, blend the chickpea flour and salt, then gradually whisk in the water to form a paste, and whisk to remove all lumps, then slowly add the rest of the water, and 2 tablespoons of the olive oil, blending well.

When the oven has reached 500°F, using oven mitts, take the cast iron skillet out of the oven, set on a heat-proof surface.

Change the oven setting from 500°F to the broiler.

Pour about 1 tablespoon of olive oil on the pan. Very gently swirl this around to evenly cover the pan, and then pour half of the chickpea batter onto the pan for two smaller pizzas, or all the batter for one large pizza, tilting a bit to distribute in a roundish shape.

Put the socca back into the oven, on the upper rack this time, and bake for about five minutes. It may take a bit longer if you are making one larger pizza. The bottom of the crust should be golden and crispy, and the top should be getting some browned spots on it.

Once this happens, remove the skillet from the oven, and place back on heat-proof surface. If I'm making two individual pizzas, I'll put a cookie sheet in the oven on the lower rack once the first pizza is baked to keep it hot while the other one bakes under the broiler.

Add your toppings, and then place the skillet back into the oven, this time on the upper rack (which should be about 6 inches away from the broiler - if it's too close to the heating element, it will start to smoke and burn your toppings).

Keep checking the pizza to see when the toppings are browned as much as you like, usually this takes less than five minutes, so this probably isn't a good time to start checking Snapchat...

When the cheese is bubbly and browning, and the socca has crispy burnt bits around the edges, it's ready!