Blue Diablo

1 oz tequila
1 dash Blue Curacao liqueur
1/2 oz lemon juice
1 dash Rose's lime juice

Colour some regular salt by adding blue food dye. (Food dye optional.) Salt the rim of an old-fashioned glass; rub a slice of citrus fruit, preferably lemon, around the rim, and then roll the edge of the glass in a saucer full of the above salt. Chill the glass by placing in fridge or freezer. When chilled, fill the glass about 2/3's full of ice. Add a shot of top-shelf tequila. Add a squeeze of lemon juice, preferably fresh, and a dash each of both lime cordial and blue curacao. Serve while the blue curacao runs down the middle of the drink.