Preheat oven to 350°. Spray a 9” round pan with cooking spray.
Whisk flower, baking powder, and salt together in a medium bowl.
Stir sugar, greek yogurt, and egg in a large bowl. Stir in milk and coffee. Stir dry ingredients into wet and stir until just combined.
Make the crumb topping: stir together brown sugar, flour, cinnamon, coffee, and butter. Add pecans, if desired.
Pour batter into prepared pan. Top with streusel. Bake for 20-25 minutes until a toothpick comes out clean.
To make the drizzle: beat butter and powdered sugar with a hand mixer until crubmly. Beat in milk and coffee until no lumps remain. Let sit for a few minutes so the bubbles can rise to the top and pop, then drizzle over cake.