In a medium skillet, on medium-high heat, cook the steak and onions about 5 minutes or until done. Drain on paper towels.
Wipe out the skillet and spray it down with non stick cooking spray. Reheat the pan back up to medium-high heat.
Pour the eggs in. Make the eggs cover the bottom. Cook until almost set and sliding a spatula under the eggs doesn't start to "scrunch" or tear the eggs up. About 4 minutes.
Flip the eggs.
Add one slice of cheese, cut/folded in half, on one side.
Add meat/onion mixture on same side.
Add the other slice of cheese on top of the meat.
Fold omelet in half. Cook another minute or two.
Slide out of pan onto plate. Top with green onions, if desired.
Notes
ITEMS/INGREDIENTS USED IN RECIPE - If you are interested in any of the items I may have used (or are similar to the items I used) in making this recipe, I have listed all or some of them above within the post. NOTE: These links are affiliate links of which I receive a small commission from the sale of certain item. This does not affect your price, it remains the same.