Step 1: Pull up a barstool. Step 2: Leave your sunglasses on. (The rays pouring through the wall-to-wall windows of this new, Central West End cantina allow for the legitimate use of indoor shades.) Step 3: Order Gringo's exquisite namesake margarita — an addictive blend of Exótico Blanco tequila, triple sec and housemade sour on the rocks. Step 4: Enjoy noshing on the complementary chips and salsa as you suck down that first margarita. Rinse and repeat for the rest of the afternoon. Remember, you're wearing sunglasses. No one can see your bloodshot eyes.