Beat eggs, milk, salt and pepper in a bowl until blended.
Wash and dry the spinach and then chopped.
Add spinach into the eggs and mix it up.
HEAT butter in 7 to 10-inch non-stick omelette pan or skillet over medium-high heat until hot. TILT pan to coat bottom. POUR IN egg mixture. Mixture should set immediately at edges.
GENTLY PUSH cooked portions from edges toward the center with inverted turner so that uncooked eggs can reach the hot pan surface. CONTINUE cooking, tilting pan and gently moving cooked portions as needed.
Sprinkle the cheddar cheese on top and serve on the plate together with whole-grain toast bread.