Spray the pan with cooking spray and place it on medium heat.

Dice the tomatoes, bell peppers, and mushrooms. Add everything in the pan and cook thoroughly.

Crack the eggs in a separate bowl and add the water & salt and pepper to it.

Beat with a fork or whisk until combined.

Pour the egg mixture on the vegetables.

Cook until your omelette is almost dry/almost cooked gently pivoting pan to ensure evenness.

Add shredded cheese to half.

Put the cheese side on plate then gently flip other side over to have half circle.