Prepare a fish dredging station with three bowls. The first bowl will contain all purpose flour, half the salt, half the black pepper all mixed together. The second bowl should contain a splash of milk mixed with a beaten egg. The final bowl should be panko bread crumbs and the rest of the salt and black pepper. Mix up all three bowls to incorporate their ingredients. 

Dry off your fish fillets very well. Season each one with salt and pepper. Using one fillet at a time, place in the flour mixture and thoroughly coat the fish, pressing the flour into all surfaces and any crevices on all sides.

Transfer the floured fish into the egg/milk mixture and make sure it gets wet and coated on all sides. 

Finally place the fish into the panko bread crumb mixture and make sure there are no visible areas where egg/milk shows through. Press panko into the fish very well, coating all around. 

Repeat for all of your fish fillets and let each one rest after dredging on parchment or a baking rack while your frying oil comes to temperature. 

In a large pot or skillet add peanut oil until it fills at least 2 inches deep in the vessel. On medium high heat bring oil up to 350 degrees. If you do not have a thermometer, heat the pot over a burner for a few minutes and sprinkle a tiny bit of flour in the oil. If it starts to bubble as soon as the flour hits the oil it should be hot enough (make a mental note that you should get a thermometer). 

Add each fillet into the oil, making sure to ease it in away from your body so that you do not splash yourself with hot oil. 

Fry in the oil for 2 minutes per side or until the crust of the fish is nice and golden brown. Once the fish is all done, move it to a plate or cooling rack to rest.

Move your fish fillets onto buns or bread. Add pickles or tartar sauce. The fast food versions of this sandwich often contain cheese, but leave that off if it doesn't sound good to you.