Fill A Large (12-Quart If You Have One) Stock Pot Two-Thirds Full With Water. Add The Tongue, Onions, Crushed Garlic Cloves, Bay Leaves, Peppercorns, And Salt. Bring To A Boil, Reduce To A Simmer, Cover, And Cook For 3 Hours, Until The Tongue Is Soft To The Touch And Tender. Remove Tongue From Water And Let Cool For A Couple Of Minutes. Notice The Light Colored Skin-Like Covering Over Most Of The Tongue. Using Your Fingers, And/Or A Sharp Small Knife, Remove This Covering And Discard. Notice The Rough Patch Of Meat Where The Tongue Would Attach To The Bottom Of The Mouth. Arturo Removes This Patch (As Does His Mother When She Prepares Tongue) Because It Is A Little Rough. It'S Perfectly Edible Though, So Keep It Attached If You Want. Slice The Tongue In 1/4-Inch Slices. (If You Are Not Preparing The Whole Tongue For Tacos, You Can Return Whatever Tongue You Do Not Slice To The Cooking Water To Soak.) Heat A Little Oil In A Frying Pan On Medium High And Saut