1 Prepare The Salsa. Either Use Store Bought Or Make Your Own. (See Above Link For Mango Salsa, Which Is Especially Good With Fish.) 2 Prepare The Cabbage And Avocado. Thinly Slice Cabbage. Put In A Small Serving Bowl. Sprinkle With Cider Vinegar (About A Tbsp) And Salt (About A Tsp). Mix In The Vinegar And Salt. Peel Avocado And Remove Seed. Chop And Reserve For Later. 3 Heat The Tortillas. Unless You Have Made Fresh Tortillas From Scratch, You Will Need To Soften Them Somehow. One Way To Easily Soften And Heat A Tortilla To Simply Heat It In The Microwave For 20-25 Seconds On High Heat, On Top Of A Napkin Or Paper Towel To Absorb The Moisture That Is Released. We Often Will Heat Two Tortillas At Once In The Microwave, Heating Them For A Total Of 40 Seconds. Another Way Is To Heat A Well Seasoned (Black) Large Cast Iron Skillet To Medium Heat. Add A Teaspoon Of Oil To The Pan Or Spread A Half A Teaspoon Of Butter On One Side Of One Tortilla. Place Tortilla In The Pan (Butter Side Down If You Are Using Butter). As The Tortilla Sizzles, Flip The Tortilla With A Spatula So That The Other Side Gets Some Of The Oil Or Butter From The Pan. Continue To Flip Every 10-30 Seconds Until The Tortillas Begins To Develop Air Pockets, About A Minute. If The Pan Begins To Smoke, Lower The Temperature. You Can Skip The Butter Or Oil If You Wish And Just Heat The Tortillas Up On The Skillet Without Them. We Have Found That The Flavor Of Packaged Tortillas Benefits From Heating Them With A Bit Of Oil. Remove The Tortilla From The Pan And Place It Folded On A Plate. If The Pan Is Large Enough You Can Prepare Two Or More Tortillas At Once. Continue Until All The Tortillas (Estimate 3 Per Person) Are Cooked. Set Aside. 4 Cook The Fish. Soak The Fish Fillets In Cold Water For At Least One Minute. Pat Dry With A Paper Towel. Heat A Large Stick-Free Skillet To Medium High Heat. Add A Couple Of Teaspoons Of Olive Oil To The Skillet. Place Fish On Skillet. Cooking Time Depends On The Thickness Of The Fillets. A Thin Fillet May Take Only One Minute On Each Side To Cook. A Thicker Fillet May Take A Couple Of Minutes. Fish Should Be Still Barely Translucent When Cooked. Break Off A Piece And Test If You Are Not Sure. Do Not Overcook The Fish. Remove From Pan When Done To A Separate Plate. Sprinkle With Salt And Pepper. 5 Assembly. I Think Tacos Are Best When You Assemble Them Yourself. Place The Plate Of Tortillas, The Plate Of Fish, The Salsa, The Cabbage, And The Avocados On The Table And Let Everyone Assemble Their Own.