Preheat your oven to 425 degrees Fahrenheit. Brush both sides of the corn tortillas with oil and lightly sprinkle with kosher salt. Place them in a single layer on a baking sheet.
Bake the tortillas for 4 minutes, then flip and continue baking for another 4 to 8 minutes, until they are golden and crispy.
Warm the refried beans in a saucepan over medium heat until heated through.
To assemble the tostadas, spread a spoonful of refried beans on each crispy tortilla, followed by a layer of guacamole.
Sprinkle shredded cheese over the guacamole and add shredded chicken on top.
Finish by adding your favorite toppings, such as shredded lettuce, pico de gallo, salsa, sour cream, queso fresco, cilantro, jalapeño slices, a drizzle of creamy cilantro-lime dressing, and a few dashes of hot sauce.
Serve immediately and enjoy your tostadas with your hands or a fork if preferred.