Preheat oven to 350°F (177°C). Grease three 9-inch cake pans, line with parchment paper rounds, then grease the parchment paper.

Whisk the cake flour, salt, baking powder, and baking soda together. Set aside.

Using a handheld or stand mixer fitted with a paddle or whisk attachment, beat the butter and sugar together on high speed until smooth and creamy, about 3 minutes.

Beat in the 3 eggs, 2 egg whites, and vanilla extract on high speed until combined, about 2 minutes.

With the mixer running on low speed, slowly add the dry ingredients. Slowly pour in the buttermilk then mix just until combined.

Pour batter evenly into cake pans.

For the cinnamon swirl: Mix the brown sugar, flour, and cinnamon together until combined. Pour the melted butter on top and mix just until combined.

Drop small spoonfuls of the cinnamon swirl on each of the unbaked cakes. Use a knife to gently swirl the spoonfuls into the batter.

Bake for around 23-26 minutes or until the cakes are baked through. Allow cakes to cool completely in the pans set on a wire rack.

In a large bowl using a handheld mixer or stand mixer fitted with a whisk or paddle attachment, beat the butter on medium speed until creamy, about 2 minutes.

Add the cream cheese one piece at a time, mixing until each has combined before adding the next.

Once the cream cheese is combined, add the brown sugar and beat on medium-high speed until combined, about 1 minute.

Add the cinnamon, confectioners’ sugar, heavy cream, vanilla extract, and salt. Beat until completely combined and creamy.

Using a large serrated knife, slice the domes off the cooled cakes to create a flat surface.

Place 1 cake layer on a cake stand, spread about 1 and ½ cups of frosting on top. Top with 2nd cake layer and spread another 1 and ½ cups of frosting on top. Top with the third cake layer.

Chill the crumb coated cake uncovered in the refrigerator or freezer for at least 30 minutes.

Spread a little extra frosting on top of the cake and use any leftover frosting to pipe detail around the edges, if desired.

Refrigerate cake for at least 30-60 minutes before slicing and serving.