01 - Combine shredded chicken with chili powder, cumin, garlic powder, salt, and lime juice in a mixing bowl. Mix thoroughly and set aside to allow flavors to meld.
02 - Warm refried beans in a small saucepan over low heat until smooth and spreadable.
03 - Place tostada shells on a serving platter. Spread a thin layer of warm refried beans evenly over each shell.
04 - Top each bean-covered shell with an even portion of the seasoned shredded chicken.
05 - Layer lettuce, diced tomatoes, red onion, shredded cheese, sour cream, cilantro, jalapeño slices, and avocado slices over the chicken.
06 - Serve immediately with lime wedges on the side for squeezing over the tostadas.