Step 1: Prepare Your Glass

1. Chill a margarita glass in the freezer for about 10 minutes to ensure your drink stays cold longer.
2. Rim the glass with cinnamon sugar. To do this, run a lime wedge around the edge of the glass, then dip it into a plate of cinnamon sugar.

Step 2: Mix the Ingredients

1. Fill a cocktail shaker with ice cubes.
2. Add the tequila, Fireball Whisky, fresh lime juice, triple sec (or Cointreau), and simple syrup (if using) to the shaker.
3. Shake well for about 15-20 seconds until the mixture is well-chilled and thoroughly combined.

Step 3: Strain and Serve

1. Strain the mixture into the prepared margarita glass filled with ice.
2. Garnish with a lime wedge and a cinnamon stick for a finishing touch.