Needless to say this recipe can be done with any white fish, but if you are in the Midwest, please try to get perch, pike or walleye for this. It just seems right. Trout would also work well, here, especially Great Lakes lake trout or steelhead.
Make sure any little bones are out of the fish. Mix everything (except the oil and salad greens) together in a large bowl. Divide the mix into 8 roughly equal parts and form into patties. If you have time, set the patties on a cookie sheet in the fridge for 30 minutes to firm up. You can skip this step if you are rushed.
Fry the patties in the butter until golden brown, about 3 to 5 minutes per side. Serve with a green salad with a nice vinaigrette, or try my saffron aioli.
If you want, you can fully cook these fish cakes, then set them on a baking sheet or plate in the freezer. Once frozen solid, put them in a freezer bag and they will be good for months. Reheat them in a toaster oven or fry them again.