A small nonstick pan with 1 tablespoon oil is heated to medium heat. Add the shallots and garlic, and cook for 30 to 60 seconds, or until fragrant.

Mushrooms should be added and sautéed until tender and slightly browned. 2 to 3 minutes.

Add the spinach and continue cooking until it barely wilts. roughly one minute. Sprinkle with a little salt and pepper. After transferring the mixture to a plate or bowl, clean the pan.

JUST Egg, flour, and baking powder should all be mixed in a small bowl. Set aside.

Reset the burner to medium-low heat, add the 2 teaspoons of oil, and swirl the pan to distribute the heat. Pour the ONLY Egg in and tilt the pan to distribute it evenly across the bottom.

When the edges start to harden, carefully run your spatula around them to prevent sticking. Once the omelette cooks and begins to fluff up a little, repeat this process a couple more times. You may slide the spatula underneath the omelette as the bottom begins to set up to determine when it's almost time to flip. Give it another minute to cook if the top is still mushy and seems prone to breaking. If it's not cooking, you can adjust the heat up a little, or down if the bottom seems to be browning too quickly. The entire procedure should just take two to three minutes.

Flip the omelette quickly and gently once the top has finished cooking. On one side of the omelette, layer the spinach and mushroom mixture, half of the cheese, then the remaining cheese. Gently fold the omelette over to seal it if the bottom has cooked. Serve after removing from heat.