Opulent Orange Manhatten Cocktail with a Twist

Ingredients:

dash of angostura bitters
1/2 ounce orange simple syrup
1 ounce Martini Rosso vermouth
1 1/2 ounces bourbon
ice

Directions:

1. In a cocktail shaker add a dash of angostura orange bitters, orange simple syrup, Martini Rosso, bourbon, and ice.
2. Use a long-handled bar spoon to stir the cocktail vigorously for 30 seconds.
3. Strain into a standard rocks glass filled with ice.
4. Garnish with Opulent Orange slices