RECIPES GROUPER Posted Mar 27, 2013 By: wfn How to Fillet Grouper Below is a step-by-step guide on how to properly fillet a grouper. Lay the fish on its side and secure it in place. Cut on an angle from the top of the head down the side, just behind the fins. Make a cut along the top of the grouper, following the spine from the head to the tail. Starting from the cut along the spine, make a long cut from the head to the tail, following as close as you can to the ribs. Repeat this cut, close to the ribs and peeling back the fillet as you go. Be cautious not to cut into the gut when you reach the bottom half of the fish. Cut the skin at the bottom of the fish to fully remove the fillet. Repeat the previous steps for the other side of the grouper.