1. Whisk together eggs and salt.
2. Heat oil in a large cast-iron skillet over medium-high heat. Add mustard seeds and turmeric; cook 30 seconds or until seeds pop, stirring frequently. Add onions; cook 30 seconds or until soft, stirring frequently. Add tomato; cook 1 minute or until very soft, stirring frequently.
3. Pour egg mixture into pan; spread evenly. Cook until edges begin to set (about 2 minutes). Slide front edge of spatula between edge of omelet and pan. Gently lift edge of omelet, tilting pan to allow some uncooked egg mixture to come in contact with pan. Repeat procedure on the opposite edge. Continue cooking until center is just set (about 2 minutes). Loosen omelet with a spatula, and fold in half. Carefully slide omelet onto a platter. Cut omelet in half, and sprinkle with black pepper.
Nutrition Note: This runs a little high in dietary cholesterol but is well within our fat and calorie guidelines.