Ingredients Cinnamon Swirl: - 1/4 cup white sugar - 2 tablespoons ground cinnamon Streusel Coffee Cake: 2 cups all-purpose flour 1 cup + 2 tablespoons white sugar 1 teaspoon salt 10 tablespoons butter or margarine, cold 1 teaspoon baking powder 1/2 teaspoon baking soda 3/4 cup buttermilk, room temperature 1 egg, room temperature 2 teaspoons vanilla extract 1 teaspoon lemon zest, optional 2/3 cup brown sugar Caramel Penuche: 1/2 cup butter or margarine 1 cup brown sugar 1/4 cup milk or dairy-free milk 1 1/4 cup powdered sugar Vanilla Drizzle: 3/4 cup confectioner's sugar 1/2 teaspoon vanilla 1/2 teaspoon ground cinnamon 1 tablespoon milk, added only as needed Instructions For the cinnamon swirl: Mix together sugar and cinnamon. Set aside. For the streusel coffee cake: Preheat oven to 350 degrees F. Grease a 10-cup bundt pan and set aside. In a large mixing bowl, whisk together flour, sugar, and salt. Cut in butter using a fork, until mixture resembles coarse crumbs. Set aside 1 cup of this mixture. Mix baking powder and baking soda into the remaining large bowl of flour mixture. Add buttermilk, egg, and vanilla, and mix vigorously until batter is smooth and fluffy, about 2-3 minutes. Gently stir in lemon zest if using. To make the crumb: Mix brown sugar into the reserved flour mixture. Sprinkle half of your crumb topping as evenly as possible into your bundt pan. Pour half of the batter into prepared pan, then sprinkle prepared cinnamon-sugar mixture over the batter, followed by the remaining crumb topping, leaving an inch around the edges so your batter can seep in. Pour remaining batter on top. Bake in preheated oven for 50-55 minutes, until toothpick inserted in center comes out clean. For the caramel penuche: In a saucepan over medium heat, melt butter. Stir in brown sugar and bring mixture to a boil for 2 minutes. Add milk, then bring to a boil again. Turn off heat and quickly whisk in powdered sugar until penuche is completely smooth. Allow to cool slightly (but not completely) before pouring over cake. For the vanilla drizzle: Combine sugar, vanilla, and cinnamon in a medium bowl. Add up to 1 tablespoon of milk (as needed to reach drizzling consistency). Drizzle over the top of your cooled coffee cake and enjoy!