Make the Tostada Shells

1. Heat vegetable oil over medium heat in a large skillet, preferably with tall sides. Tear off a tiny piece of tortilla and add it to the skillet. If the oil starts to bubble around the tortilla piece, it's ready to go!
2. Fry up tortillas one at a time, about 30 seconds to 1 minute each side, depending on how dark and crispy you like them. I prefer mine very crispy and quite dark so did a full minute on each side.
3. When done to your liking, remove the tortillas from the skillet to a wire rack or a plate covered in paper towels to absorb the excess oil. Sprinkle each shell with a pinch of salt and chili powder as soon as you place it on the rack. Let cool.

Make the Fillings

1. Combine all the ingredients for the mango salsa, except the garnishes, in a small bowl. Set aside.
2. Toss together all the ingredients for the cabbage slaw in a medium bowl. Set aside.
3. In a medium pot, melt butter over medium high heat. Pour in black beans and gently mash about half of them. Stir in the rest of the ingredients for the black bean filling and mix until combined. Cook until heated through.

Assemble the Tostadas

1. Spread a layer of the bean filling on each tostada shell.
2. Top with bean layer with a few spoonfuls of cabbage slaw.
3. Sprinkle with mango salsa. Garnish with crumbled queso fresco, jalapeño slices, avocado and fresh cilantro leaves.