Take the bavette steak out of the refrigerator and let it come to room temperature for about 30 minutes.
Preheat your cast iron skillet over medium-high heat. Add the olive oil and allow it to heat until shimmering.
Season the steak generously with salt and pepper on both sides. Once the skillet is hot, add the steak and sear for about 4-5 minutes on each side for medium-rare.
Remove the steak from the skillet and let it rest for at least 5 minutes.
In the same skillet, reduce the heat to medium and add the minced garlic. Sauté for about 1 minute until fragrant.
Carefully pour in the whiskey, scraping the bottom of the skillet to deglaze. Allow the whiskey to simmer for about 2-3 minutes until it reduces slightly.
Stir in the heavy cream, Dijon mustard, and Worcestershire sauce. Let the sauce simmer for another 3-4 minutes until it thickens slightly.
Slice the rested steak against the grain into thin strips. Serve topped with the whiskey garlic cream sauce and garnish with chopped parsley.