In a medium bowl, whisk together the chickpea flour, water, 1 tbsp olive oil salt, ground coriander and turmeric.
Cover with plastic wrap and let rest for at least 2 hours.
Add 1 tsp olive oil in a 10-inch oven-safe skillet and cook the onions until they begin to brown. Add in the tomatoes and cook for a few minutes. Add the minced garlic clove and cook for another minute.
Stir the vegetables into the chickpea flour mixture.
Heat the broiler on low and grease the skillet you just used with 1 tsp olive oil. Pour in half of the batter and place it in the oven, 7-8 inches from the broiler, and cook until the sides of the socca begin to brown. This could take anywhere from 5-15 minutes depending on the strength of your broiler, so keep an eye on it to ensure it doesn’t burn. Be careful not to reflexively touch the handle of the skillet when you remove it from the oven. Use an oven mit!
When ready, slide the first socca onto a cutting board to cool, add another tsp olive oil and swirl it around to grease the pan, and pour in the remaining batter to cook the second one.
When cooked, cut into slices and serve as a side for curry dishes.