Combine the chickpea flour and all the dry ingredients in a bowl, add water and stir until the batter is smooth. Add chopped spinach and stir again.
Heat a frying pan over medium heat. Pour the batter into the pan, as if making pancakes. Sprinkle some mushrooms and onions on the top of the batter as it cooks.
When the underside is browned, flip the omelette and cook for another few minutes, repeat if necessary.
Let cool slightly, serve and enjoy

1 cup chickpea flour
1 cup lukewarm water
1/3 cup nutritional yeast
1/2 teaspoon baking soda
1 teaspoon turmeric
A pinch of black salt and black pepper
A handful of finely chopped spinach
1 cup mushrooms, sliced
1 onion, diced