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This rich and smooth Spiced Bourbon Vanilla Slammer combines bourbon, vanilla, angostura aromatic bitters and a quick and easy fennel seed simple syrup for a deliciously simple cocktail for all seasons.


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A cocktail for all seasons

Winter, spring, summer or fall- this cocktail has everything you need for a great happy hour cocktail with friends! This Bourbon Vanilla Slammer takes classic bourbon whiskey, pure vanilla extract, a few dashes of tart and citrusy angostura aromatic bitters, fresh squeezed lemon juice and a quick and easy fennel simple syrup- and transforms them into a bold, refreshing cocktail that’s super easy to whip up on the fly!

spiced fennel vanilla bourbon slammer cocktail

Making the Fennel Simple Syrup

To make the fennel simple syrup- all you will need is some fennel seeds, sugar, water, and about 5 minutes (plus cooling time).

Throw everyone in the pool (aka the saucepan) and let them meld together into a richly colored, deeply flavored syrup. Once it’s cooled and strained, it’s ready to use- and store in the fridge for up to 2 weeks.

vanilla cocktail

Making the cocktail

This recipe serves 1, however- it’s super easy to make these cocktails in batches, or to make several at a time. To make the Spiced Bourbon Vanilla Slammer, you will need:

  • A bit of the super easy fennel simple syrup.
  • Some of your favorite Bourbon whiskey.
  • A bit of pure vanilla extract.
  • A few dashes of angostura aromatic bitters.
  • The juice of 1 lemon.
  • A bit of seltzer or sparkling mineral water, to top the cocktail.

Simply add everything but the seltzer or sparkling mineral water to a shaker or mason jar, shake well and pour over ice. Top with a bit of your bubbly water of choice and garnish with a bit of lemon. Cheers!

bourbon cocktail with vanilla and bitters

Want to give this recipe a try? 


If you make my Spiced Bourbon Vanilla Slammer, please be sure to leave me a comment! I would love to hear from you, and value your feedback! Lastly, if you make the recipe and love it, please tag me on Instagram! I love to see your photos!

Looking for more great sandwich ideas? Why not try my Fennel Grapefruit Vodka Fizz, Gin Honey Bee, Honey and Thyme Paloma, or Nectarine and Basil Bourbon Spritz!

bourbon vanilla slammer

Spiced Bourbon Vanilla Slammer

Prep Time20 mins
Total Time20 mins
Course: cocktail
Keyword: bitters, bourbon, fennel, vanilla
Servings: 1


  • 2 oz fennel simple syrup
  • 1.5 oz bourbon
  • 1/4 tsp pure vanilla extract
  • 2 dashes Angostura bitters
  • the juice of one lemon
  • top with seltzer water or sparkling mineral water 

Fennel Simple Syrup

  • 1/2 tsp fennel seeds
  • 1 cup water
  • 1 cup cane sugar


  • Make the fennel simple syrup. Add the fennel seeds, sugar and water to a small saucepan. Bring to a boil, then reduce heat to medium and simmer for 5 minutes, stirring occasionally until sugar is fully dissolved. Once sugar is dissolved and syrup is slightly thickened, turn off heat and allow to cool to room temperature.
    2. Strain into a jar or airtight container and store in the refrigerator until ready to use. Makes about 1.5 cups, and keeps up to 2 weeks in refrigerator.
    3. Make the cocktail. Add fennel syrup, bourbon, vanilla, bitter and lemon juice to a cocktail shaker or mason jar and shake vigorously. Fill a cocktail glass with ice, and pour over. Top with seltzer water or sparkling mineral water. Garnish with lemon wedge, of desired. Cheers!


You can also make my Fennel Grapefruit Vodka Fizz with the fennel simple syrup!

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