Cinnamon Cake

1. In a large mixing bowl, beat the softened butter with the granulated sugar and brown sugar until the mixture looks light and creamy.
2. Add the eggs one at a time, mixing well after each, then stir in the vanilla. In another bowl, sift together the flour, baking powder, baking soda, salt, and ground cinnamon.
3. Add these dry ingredients to the butter mixture in three parts, alternating with the buttermilk.
4. Start and finish with the flour, and mix only until everything is blended.
5. Divide the batter into the prepared cake pans lined with parchment paper.
6. Smooth the tops with a spatula and bake in a preheated oven at 160°C (320°F) for about 40 minutes, or until a toothpick inserted in the center comes out clean.
7. Let the cakes cool completely before assembly.

Cinnamon Sugar Syrup

1. Place the water, brown sugar, cinnamon, and vanilla in a small saucepan.
2. Cook over medium heat, stirring often, until the sugar is dissolved and the syrup lightly coats the back of a spoon.
3. Remove from the heat and let it cool to room temperature.

Cinnamon Buttercream

1. Prepare the frosting following my cinnamon buttercream recipe. Keep it at room temperature until ready to use.

Cream Cheese Filling

1. In a mixing bowl, whip the cream cheese with the powdered sugar until smooth.
2. Add the heavy cream and vanilla, then beat on high speed until the mixture becomes light and fluffy, almost like a thick whipped cream.

Assembly

1. Place one cake layer on a serving plate. Brush the top with a few spoonfuls of the cinnamon syrup.
2. Pipe a ring of cinnamon buttercream around the edge to hold the filling in place, then spread some cream cheese filling inside the ring.
3. Drizzle a little more syrup over the cream cheese layer.
4. Repeat with the next cake layers.
5. Once all the layers are stacked, spread a thin layer of buttercream over the whole cake (this is the crumb coat) and chill for 20 minutes.
6. Finish with a thicker coat of buttercream, smooth the sides, and decorate the top with a piping bag. Sprinkle ground cinnamon on top before serving.