In a small bowl, combine black beans with salsa verde. Set aside.
Heat a griddle to 350º. Coat griddle with olive oil or butter. Place three corn tortillas on griddle and turn to coat with oil.
On one tortilla, place 1/4 cup of pepper jack cheese. Top with 1/4 cups of bean/salsa mixture.
On second tortilla, place 1/4 cup cheddar cheese and top with 1/2 an avocado, sliced. When cheese begins to melt, stack the third tortilla on top.
Meanwhile, crack egg on the corner of the griddle and allow it to cook to desired doneness.
When the pepper jack cheese is completely melted, stack the cheddar/avocado layer on top.
Remove from heat and top with fried egg, tomatoes, cilantro and green onion. Season with salt and pepper to taste.