01 -
Bring butter, eggs, milk and sour cream to room temperature (about 1 hour). Mix 1 tablespoon of coffee grounds into the milk and let it infuse while other ingredients come to temperature.
02 -
Melt the butter in a medium bowl. Mix in brown sugar, flour, cinnamon, and crushed pistachios with a fork until small clumps form.
03 -
Preheat oven to 350°F (175°C). Butter a 9-inch cake pan and line with crinkled parchment paper, pressing it up the sides to create handles for easy removal.
04 -
Whisk together flour, baking powder, and salt in a small bowl.
05 -
Beat butter and sugar until light and fluffy, about 3-4 minutes, using either a hand mixer or stand mixer with paddle attachment.
06 -
Beat in eggs and vanilla for 1 minute until well combined.
07 -
Gently fold in half the flour mixture, then mix in the coffee milk and sour cream, followed by remaining flour mixture.
08 -
Pour half the batter into the pan, top with 1/3 of the streusel, add remaining batter and finish with remaining streusel. Bake 40-50 minutes until a toothpick comes out clean.
09 -
Whisk powdered sugar with espresso until smooth. Once cake is completely cool, drizzle with glaze before serving.