In a small sauce pan, boil together 1 cup sugar and 1 cup water to make a simple syrup
As soon as the sugar is dissolved in the water, add the cilantro and 3 of the Jalapeno slices and continue to boil the syrup for 2 more minutes, then lower the heat and cook 2 more minutes to reduce the syrup.
Remove from heat and allow to cool (Syrup should stay in the fridge for up to 30 days)
Take your wedge of lime and rub the lip/rim of the glasses
Turn glass upside down and dip into the chili lime sugar to coat the edge
Fill the glass 3/4 full with ice.
In a shaker, add the lime juice, tequila & Cointreau (or limeade and soda water) and the cilantro jalapeno syrup. close the shaker and mix thoroughly for 30 seconds and pour over the ice in the glass.
Garnish with lime wedge and a slice of the jalapeno
Enjoy