Step 1

In the bowl of a food processor, place the flour, brown sugar, espresso powder, cinnamon and salt. Pulse until combined. Add the cold cubed butter and whiskey. Pulse until pea-sized clumps of streusel form. Refrigerate until ready to use.

Step 2

For high altitude adjustments, please see the instructions in the "Notes" section below!

Step 3

Preheat oven to 350°F. Spray a 9-inch baking pan with cooking spray and line with parchment paper, letting the excess hang off of the sides of the pan. Set aside.

Step 4

In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl with a hand mixer, beat the butter and granulated sugar on medium speed until fluffy (about 3 minutes). Add the eggs one at a time and beat after each addition.

Step 5

In a medium bowl, whisk together the flour, baking powder, baking soda and salt. In a liquid measuring cup, whisk together the buttermilk, whiskey, 2 tbsp. of the espresso powder and vanilla extract until the espresso powder is dissolved.

Step 6

With the mixer on low speed, gradually add the flour mixture to the butter mixture, alternating with the buttermilk mixture. Begin and end with the flour mixture. Beat until just combined, but do not overmix.

Step 7

Spoon half of the batter into the prepared baking pan and top with half of the whiskey spiked streusel and remaining 1 tbsp. of espresso powder. Top with the remaining batter and spread very carefully with a knife or offset spatula. Cover the top of the batter with the remaining half of the whiskey streusel (squeeze the streusel together to form larger clumps as you sprinkle on top of the batter).

Step 8

Bake for 45 minutes until a wooden toothpick inserted in the center comes out with a few moist crumbs. Let coffee cake cool in the pan on a wire rack. Slice and enjoy!