In the cocktail shaker, add the tequila, Patron orange liqueur and all but 1-2 slices of the jalapeno. Using the muddler, mix the ingredients well. Allow to rest for 5 minutes.
Add the remaining ingredients to the shaker along with several ice cubes and place the cap on the shaker.
In one shallow dish, add 2 ounces of lime juice and in the other, add the salt and chili powder.
Place your glass, rim side down in the lime juice and then in the salt/chili powder dish.
Add 3-4 ice cubes to your margarita glass, pour the margarita mixture into the glass and garnish with a jalapeno slice.