Courtesy of Ray Bond in Singapore. The is the rough recipe as I remember it. Given that there is tequila involved, the memory may not be quite accurate.
In a blender mix:
2 ounces DECENT Tequila
1 Ounce Cointreau
3/4 inch lemon cordial
3/4 inch lime cordial
Fill to just below half mark with ice. Blend until smooth. Dip glass into lime juice, then roll edge in salt. Pour drink into glass. Give keys to DD. Enjoy.
1) DECENT tequila – i.e. Jose Cuervos or better. No need to go over the top. You can use Mescal, but you get a much rougher taste. You can also use a much better Tequila, but in my opinion, if you are going to buy good tequila, you should be drinking it straight.
2) Do not substitute Triple Sec for Cointreau.
3) If you cannot find lemon and lime cordial, substitute lemon and lime juice if possible.