Sour Cream Streusel Coffee Cake | Savor Recipes

Ingredients

• 2 cups all-purpose flour
• 1 teaspoon baking powder
• 1/4 teaspoon salt
• 6 tablespoons cold unsalted butter, cut into small pieces
• 3/4 cup packed light brown sugar
• 1/2 cup sour cream
• 1 large egg
• 1 teaspoon vanilla extract
• 1/2 cup old-fashioned oats
• 1/2 cup chopped walnuts
• 1/2 cup all-purpose flour
• 1/4 cup packed light brown sugar
• 1/4 teaspoon ground cinnamon