This ceviche tostada recipe is made using yellowtail or ahi tuna. However, ceviche can be made with a wide variety of fish.  Technically, you can make ceviche with any variety of fish, but the best are mild in flavor, white-fleshed ocean fish with a semi-firm texture. Popular choices include sea bass, halibut, grouper, snapper, or flounder. You can also make ceviche (and ceviche tostada) using shrimp!