Cream Cheese Filling:

1. In a stand mixer fitted with the paddle attachment, beat the cream cheese with the granulated sugar on medium speed until smooth and lighter in texture.
2. Wipe down the bowl and beater. Add the egg, cinnamon, vanilla, and salt and continue to beat on medium-high speed until smooth, wiping down as needed. Transfer to a separate bowl and place in the fridge to chill while preparing the cake batter.

Pumpkin Bundt Cake:

1. Preheat oven to 350° F. Grease a 12-cup bundt pan with non-stick cooking spray, making sure to cover all the grooves in the pan.
2. In a large bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, all spice, cloves, ginger, and nutmeg.
3. In the bowl of a stand mixer fitted with the paddle attachment, cream together the butter and sugars on medium speed until smoothly combined. Beat in the eggs, one at a time, until smoothly incorporated, wiping down the bowl and beater after each addition. Add the pumpkin, oil, sour cream, and vanilla and beat in until the mixture is smooth, wiping down the bowl and beater as needed.
4. Add the dry ingredients to the wet and mix in a lowest speed just until mostly incorporated. Finish folding the batter together by hand just until fully incorporated. The batter will be thick.
5. Pour half of the pumpkin batter into the prepared bundt pan, making sure the batter covers the bottom of the pan and fills every crevice. Smooth out the top with the back of a spatula. Add the cream cheese filling to cover the first layer of batter, again reaching every crevice and smoothing on top. Repeat with the remaining pumpkin batter, covering the cream cheese completely. Rap the pan firmly against the counter to release any air pockets and ensure that the batter settles into the pan.
6. Bake the bundt cake in the preheated oven for 55-60 minutes, until a toothpick inserted into a center section of the cake comes out clean. Let the bundt cool in the pan for 15 minutes, and then transfer to a wire rack to cool fully before glazing.

Cinnamon Brown Sugar Glaze:

1. Combine butter and milk in a microwave-safe liquid measuring cup or small mixing bowl (preferably the former, since it has a spout for pouring). Microwave for 40 seconds, or until the butter has melted. Add the brown sugar and whisk in until it has melted and the mixture is smooth. Whisk in the confectioner's sugar and cinnamon until smooth. The glaze should be somewhat thick but still fluid enough to pour.
2. Pour the glaze carefully over the top of the cooled cake. For best presentation, serve cake the day it is made. Store any leftovers in the fridge in a covered container***, or covered with plastic wrap.