Cut a parchment paper sling slightly smaller than the width of the cake pan and make sure it fits flatly in the bottom. Then lightly spray the bottom and sides of the pan with a vegetable oil based spray. Place you parchment paper sling in the bottom of the pan and smooth it out so that it sticks to the pan spray (you can use metal binder clips to secure it to the pan).
In a large bowl, whisk together the browned butter, brown sugar and sugar until combined.
Then add in the eggs, vanilla, and pumpkin until fully combined and smooth.
In a separate bowl, whisk together the flour, pumpkin spice, baking powder, baking soda, and salt.
Alternate folding in half of the dry ingredients and yogurt, then mix until just combined. The batter should be smooth but very thick.
In a medium bowl, mix together all of the streusel ingredients until it comes together and forms clumps. Use your hands to form larger clumps if desired.
Spoon half of the coffee cake batter into the bottom of your pan and spread into a smooth layer. Sprinkle half of the streusel in an even layer over the batter. Top with the remaining batter and then sprinkle with the rest of the streusel.
Bake at 350°F for 45-55 minutes or until a cake tester comes out clean. If the streusel begins to brown too quickly, cover with foil for the remainder of the baking time.
Remove from the oven and let cool completely in the pan before removing.
To make the glaze, whisk together the powdered sugar, melted butter, and vanilla. Add milk 1 teaspoon at a time until desired consistency is reached.
Drizzle the glaze over the top of the pumpkin spice coffee cake and enjoy!
Notes
Brown the butter: In a small saucepan, melt butter over medium heat. Once melted, stir frequently and watch closely for the formation of brown specs on the bottom of the pan and a nutty aroma. Once you see brown specs, stir for just a few more seconds (it browns super quickly). Remove from the heat and immediately pour into a different bowl to prevent it from burning. Let cool before using. If you don't want to use browned butter you can just use room temperature butter. Note: For every ½ cup (1 stick or 113g), you'll lose about 1 tablespoon (14g) to evaporation while cooking. So you can either add in an extra 1 tablespoon before browning, or if you're browning big batches, just make up the weight difference in your recipe with regular unsalted butter if needed.Store in an airtight container at room temperature for up to 5 days.