Whisk chickpea flour, water, nutritional yeast, baking powder, garlic powder, onion powder, turmeric, kala namak and 1 ½ teaspoons of oil in a small bowl until smooth. Let stand for 5 minutes.
Heat the remaining 1 ½ teaspoons oil in a medium nonstick skillet over medium heat; swirl to coat the pan.
Pour in the chickpea mixture. Cook, undisturbed, until the top is covered in bubbles and looks dry, about 4 minutes. Remove from heat.
If desired, spread toppings of choice over half of the omelet. Using a spatula, fold the omelet over the filling (or simply fold the omelet in half, if not using toppings).
Cover the pan; let stand to steam for 5 minutes.
Slide the omelet onto a plate to serve.