In a small saucepan, combine refried beans with water, minced onions and garlic. Heat over low heat, and stir until well mixed with a smooth, medium-thick consistency. Set aside.
In a larger nonstick skillet, heat tortillas: Lightly spray each side with cooking oil and heat 1 to 2 minutes per side. Remove from heat, and keep warm (or warm the tortillas in the microwave, first wrapping them in a moist paper towel).
Using the same skillet, lightly spray again with the cooking oil spray. Carefully crack each egg (this may be easier to do two at a time) and cook sunny-side up, or scrambled if you prefer.
When the eggs are almost done, turn off the heat under the skillet and assemble the tortillas. Place two tortillas on each plate. Mound about 2 tablespoons of the bean mixture on each tortilla. Place two eggs on top, and top with about 2 tablespoons of green chile sauce (or diced green chiles) and a small slice of avocado.