Heat up the oil in a large skillet.
Add the onion, jalapeno, tomato, and spinach
Cook for 3-4 minutes, or until the spinach is soft.
Remove from the skillet.
Melt butter in the same skillet.
Whisk the eggs and add to the skillet.
Cook for 30 seconds.
Lift the sides so the uncooked egg cooks.
Then add the cooked spinach mixture to one half of the egg.
Add the cheese.
Fold the other half over the filling.
Cook for another 2 minutes, or until the egg is fully cooked.
Top with chopped cilantro and sliced avocado.
Serve with toast or crispy potatoes.