In a mixing bowl, melt some butter and stir in a splash of Irish whiskey. Immerse sirloin steaks in this marinade, coating thoroughly, and let sit in the refrigerator for at least 3 hours.

Heat a cast iron skillet over medium-high heat. Remove the steak from the marinade, allowing excess to drip off. Sear for about 3-4 minutes per side until browned.

Transfer the steaks to a preheated oven at 350°F (175°C). Bake for approximately 10 minutes or until desired doneness is reached.

While the steaks are baking, peel and chop the potatoes. Boil in salted water until tender, about 15-20 minutes. Drain and mash them until smooth, adding in pre-cooked kale and seasoning with salt and pepper.

Using the same skillet, reduce heat to medium and add chopped shallots. Sauté until translucent, about 2 minutes. Deglaze the pan with whiskey and let reduce for 1-2 minutes. Pour in heavy cream and simmer until thickened.

To serve, create a bed of colcannon on each plate, place a steak on top, and drizzle with whiskey cream sauce. Garnish with freshly chopped parsley.