Since I was raised on wonderfully lardy, cheesy Tex-Mex, it took me a while to come around to the ungloppy goodness that is a fish taco. In the early 1990s fish tacos became something of a craze in Houston, if I remember correctly, but I was not on board. In my wisdom and maturity today, however, I embrace all foods Mexican or Mexican-ish, including tortillas (corn or flour) full of fish (fried or grilled) and slaw (or salsa, or avocados, or whatever feels right).
This is the sort of thing a competent and intuitive cook can put together with no recipe. I have made brilliant fish tacos off the top of my head, but I have also made some less satisfying ones, with poorly cooked fish or unbalanced flavors. When I can get it right every time, I will know that I have arrived as a home cook. Until then, I rely on recipes to reorient me when I get off track. This is my current favorite. It's fast and fairly healthy but always feels somehow celebratory to me.
Instead of tilapia, I use the cheapest wild-caught flaky white fish available. I never cut the fish into strips before cooking. Plain yogurt (which I always have at home) is a perfectly acceptable substitute here for sour cream (which I never do).