Step 1

Preheat your oven to 350 degrees F and grease a 9x13 baking dish.

Step 2

Start by making the cake. Add the flour, brown sugar, baking powder, vanilla, eggs, milk, and sour cream into a large bowl. Stir everything together well to form a smooth batter.

Step 3

While stirring, slowly pour in the melted butter. Mixing the butter in a little bit at a time will help blend it well without causing the batter to separate.

Step 4

Pour the cake batter into your baking dish and spread it into an even layer in the pan.

Step 5

Next, make the cinnamon filling. Mix all of the ingredients for the cinnamon filling together in a medium-sized bowl. The mix will look thick and sugary.

Step 6

Scoop spoonfuls of the cinnamon filling and drop it onto the cake batter. Put dollops of the cinnamon filling evenly across the surface of the cake batter until you have used all of the cinnamon filling.

Step 7

Run a butter knife through the cinnamon filling and cake batter, swirling them together. Try to make a spiral or marble effect as you swirl the knife through the batter. You do not want to over-mix the cinnamon into the batter but keep the defined swirls.

Step 8

Bake the cinnamon roll cake in the preheated oven for 35 minutes. The top will be a light golden brown and a toothpick inserted into the center of the cake will come out clean.

Step 9

Let the cake cool for about 10 minutes while you make the glaze.

Step 10

To make the cinnamon roll glaze, whisk the powdered sugar, milk, melted butter, and vanilla together in a medium-sized bowl. Pour the glaze over the cinnamon roll cake, spreading it across the entire top of the cake.

Step 11

Slice the cinnamon roll cake and enjoy while warm!