Preheat oven to 400 degrees F. and place 4 tostada shells onto a baking sheet. Heat for 3-5 minutes until hot. Remove and cover with foil until eggs are cooked. Place refried beans into a heat proof bowl, loosely cover and microwave for 90 seconds or until hot. Stir and set aside for a few minutes.
Heat a skillet over medium heat and melt butter, swirling to coat pan. Crack eggs into pan and season with salt and pepper. Cook until whites are mostly set.
Use a butter knife or offset spatula to spread refried beans carefully and evenly over warm tostada shells. Leave a small border around edges.
Top each tostada spread with warm refried beans with cooked eggs.
Spoon pico de gallo or salsa over tostadas and serve warm.
Video
Notes
I like to heat up my skillet a few minutes before adding the butter and eggs. Cooks the eggs nice and fast.
Once tostada shells and beans have been warmed, keep the oven on warm and place them in the oven until eggs are done cooking.
Use your favorite Mexican toppings for your tostadas. Other ideas are guacamole, shredded cheese, green onions, sliced jalepenos and even bacon crumbles.