Coffee Cake Recipe - Sour Cream Coffee Cake with Streusel

Name: Coffee Cake Recipe - Sour Cream Coffee Cake with Streusel
Prep time: 30 min
Cook time: 50 min
Total time: 1 h 20 min
Cuisine: European, German
Ingredients: 3/4 cup light brown sugar, packed; 2 teaspoons ground cinnamon; 1¼ cups all-purpose flour; 1/3 cup chopped pecans or walnuts (optional); 1 tablespoon ground cinnamon; 1/4 teaspoon kosher salt; 8 tablespoons (1 stick) unsalted butter, melted and cooled; 2 cups all-purpose flour; 1½ teaspoons baking powder; 1/2 teaspoon baking soda; 3/4 teaspoon kosher salt; 8 tablespoons (1 stick) unsalted butter, softened; 1 cup granulated sugar; 2 eggs, room temperature; 1 cup sour cream, room temperature; 1/4 cup milk, room temperature; 2 teaspoons pure vanilla extract; 2/3 cup chopped pecans or walnuts (optional); powdered sugar, for dusting