For tostada shells, place tortillas in a single layer on the middle oven rack. Bake in a 350* oven for 6 minutes, turning halfway through baking time or till golden and crisp. (If they bubble, prick with fork.).
Set aside and cover to keep warm.
Meanwhile, in a medium skillet,cook and stir chicken or turkey and chili powder over medium heat till chicken is tender and no longer pink.
Stir in salsa.
Set aside; keep warm.
Drain beans, reserving liquid.
In a small saucepan, stir beans over low heat until heated through.
With a potato masher or fork, mash beans with reserved liquid till of spreadable consistency; heat through.
To assemble, place warm tortilla on plate, spread with thin layer of beans, chicken, and so forth.