Place sliced cabbage in a colander and sprinkle with ½ tsp. of salt. Toss and massage lightly to distribute salt evenly. Let stand for 20 minutes. This will season the cabbage, as well as make it slightly softer and even sweeter. Make the dressing by whisking the rice vinegar, olive oil and honey together in a bowl. Set aside until later.
Place edamame and chicken stock in a small pot and when it comes to a boil, cook uncovered for 2 minutes. In a food processor, add the coarsely chopped garlic and edamame, along with all of the broth. Pulse until nicely pureed. Add softened cream cheese and wasabi paste. Puree again for about 1 minute or until the mixture is smooth and slightly thickened, like hummus.
Season both sides of the tilapia filets lightly with salt and pepper. In a large skillet, add a little olive oil and place over high heat. Add the tilapia, but work in batches, as to not overcrowd the pan. Saute for 3 minutes on the first side, then 2 minutes on the second side. Remove to a plate or tray and keep warm with aluminum foil until all the batches are done.
Arrange the tostadas on individual plates. Place some edamame puree on top of each one. Add the tilapia filets. Toss the softened cabbage with the dressing and place a nice mound on top of each of the filets. Sprinkle with chopped cilantro and serve with lime wedges. To eat, squeeze fresh lime juice on top and break the tostada apart with a fork. Eat everything with a fork, or use your fingers and enjoy as fancy nachos!