Whisk the chickpea flour, water, salt and 1 ½ tablespoons oil together in a medium bowl. Let the batter rest at least half an hour at room temperature to give the flour time to absorb the water.

Position an oven rack 6-8 inches under the broiler and turn on your oven’s broiler. Pour 1 tablespoon oil into a 10-inch cast iron or other oven-safe skillet and swirl to coat the bottom of the pan. Place the skillet in the oven for a few minutes to heat up.

Carefully remove the skillet from the oven with oven mitts and pour the batter into the hot skillet. Tilt the pan to spread the batter evenly over the surface.

Place the skillet under the broiler and cook 5-8 minutes, until the socca is set and the edges start to brown. Carefully remove the skillet from the oven.

Spread the hummus evenly over the surface of the socca with a spatula, leaving a ½-inch border. Toss the spinach with ½ teaspoon olive oil to coat the leaves. Scatter the spinach, roasted red peppers, olives and feta cheese on top of the hummus.

Return the skillet to the oven and broil for 3-4 minutes until the ingredients are heated through. Remove the skillet from the oven and let cool for a couple of minutes. Then cut socca into slices or wedges and serve.