Preparation Steps

• Preheat oven to 350°F. Line 2 baking sheets with parchment paper.
• Make streusel: In a bowl, combine flour, granulated sugar, brown sugar, cinnamon, and salt. Stir in melted butter until clumps form. Chill while you make the dough.
• Cream softened butter, granulated sugar, and brown sugar with a mixer on medium until light and fluffy, about 2 minutes.
• Beat in egg, vanilla, and sour cream until smooth. Scrape bowl.
• Whisk together flour, baking powder, baking soda, and salt. Add to wet ingredients and mix on low just until a soft dough forms; do not overmix.
• Scoop dough into 2 tablespoon portions and place 2 inches apart on prepared sheets. Gently press a shallow well in the center of each scoop.
• Fill each well with a heaping teaspoon of streusel and sprinkle more streusel over the top, pressing lightly so it adheres.
• Bake 11 to 13 minutes, until edges are set and tops look dry but centers are still soft. Rotate pans halfway through.
• Cool on the sheet for 5 minutes, then transfer to a rack to cool completely.
• Make glaze: Whisk powdered sugar, milk, vanilla, and espresso powder until smooth and pourable. Adjust with a splash of milk if needed.
• Drizzle glaze over cooled cookies and let set for 15 minutes before serving.