Drain and rinse the black beans and set aside.

Heat a well-seasoned cast iron or non-stick skillet over medium to medium-high heat. Add the shredded potatoes, onions, and bell pepper. Allow to cook, flipping occasionally. After several minutes, add the mushrooms and continue to cook. Once your desired crispiness is achieved, transfer to a bowl.

Keep the same skillet heated to soft-fry the egg. Crack the egg into the center of the skillet and allow to cook until the white is cooked but the yolk is not completely set. Transfer the cooked egg onto the hash brown mixture. Top with the black beans, pico de gallo or salsa, and sliced or diced avocado. Garnish with fresh cilantro if desired.