Thanks for bringing tilapia up, Katie. I've been meaning to pick some up because it seems like it's always on sale and I keep seeing it brought up here.
Until I do..... I buy frozen orange roughy when it's on sale. You can get a big, fill your plate sized filet for $4 something. A little cooking spray in a glass baking dish, a sprinkling of dill on the filet, bake until it flakes... mmmm.
Or a really easy way and one of my favorites is to season one side with a lot of cajun seasoning, get a skillet going on the stove hot, hot, hot (I use CI, do NOT use non-stick), throw in some butter and as soon as it melts, which should take about 3 seconds, put the filet in. Then season the other side of it. Flip it pretty quickly. I don't time, but when the side in the butter is backened but not not burned, it's time to flip. I would be surprised if it was more than two minutes. This cooks so fast it's hard to mess it up. I've been meaning to try this with tilapia. I call it blackened fish, but I don't know if it is in the true sense of the term.
And can you believe perch was 15.78/lb in the store a few days ago! That's outrageous. I gotta get me a boat again.