This is such a nice cocktail! We had a couple of these after our Burns' night feast, which was a HUGE success by the way, I've updated my post with the changes I made included the incredible Whiskey Gravy I made to go with it - a new favourite for sure :-)
This is based on a recipe on the Cointreau website called the "Silent Third" (haha, great name!) but I've swapped the lemon juice with lime (much better) and upped the Cointreau just a tad which I feel balances out the sweet / sour aspect of the drink perfectly. Just a warning though - they are VERY drinkable and quite the hit!
• 1.5 fl oz Cointreau
• 1 fl oz Whiskey (I always use Jameson's)
• 1 fl oz fresh lime juice, pulp strained out.
Fill a cocktail shaker halfway with ice cubes and add all the ingredients. Shake very well then strain into a martini glass. Sláinte!