Pre-heat the oven to 350ºF.

Line a 8” or 9” springform cake pan with parchment paper and spray it with oil. If using a 8" pan, make sure it's at least 3 inches deep.

Place the butter, brown sugar, cinnamon powder, and flour together in a bowl. Beat the mixture using an electric mixer for 1 to 2 minutes, until smooth. Place the mixture in a piping bag, or in a ziplock bag, and snip the end with scissors.

In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon. Set it aside.

In a large mixing bowl, or in the bowl of a stand mixer, beat the butter at medium speed for 30 seconds.

Add the sugar and the vanilla bean seeds to the bowl, and beat together with the butter for another 2 minutes, until the mixture is light and fluffy.

Scrape the bowl every so often to ensure everything is getting nicely incorporated together.

Add the eggs, one at a time, mixing until incorporated before adding the next egg.

Add the vanilla and mix to combine.

Add the sour cream and mix until incorporated.

Add half of the dry ingredient mixture to the bowl and mix on low to combine.

Pour the buttermilk in and mix.

Add the remaining dry ingredient mixture and mix on low to combine. You can also use the spatula instead of the mixer to fold the batter during this final stage. Avoid over mixing, to prevent the cake from turning out dry.

Pour half of the batter on the bottom of the prepared pan. Use a spatula to spread it evenly.

Pipe a swirl of the cinnamon filling on top of the batter.

Top with the remaining batter and use a spatula to smooth it out.

Pipe another swirl of the cinnamon mixture over the batter. Tap the pan against the counter a few times.

Bake the cake in pre-heated oven for about 40 to 45 minutes. If the top of the cake is browning too much towards the end, and the center is not yet cooked, cover it with a piece of aluminum foil.

You will know the cake is done baking when you touch the top of the cake and doesn’t feel soft or jiggly underneath. Insert a toothpick in the cake, and should come out clean, without any gooey batter attached.

Remove the cake from the oven and let it cool down completely.

In a small bowl, add the cream cheese and butter. Beat with a hand mixer for 30 seconds.

Add the powdered sugar and mix on low.

Add the milk and vanilla, mix to combine.

If the glaze is too runny, add more powdered sugar and stir. And if the glaze is too thick, add a bit more milk, one teaspoon at a time until the perfect consistency is achieved.

Once the cake has cooled down, drizzle the glaze on top, slice and serve.