1-Preheat the oven to 350ºF: Preheat the oven to 350ºF. Line 9 x 9-inches pan with baking paper leaving large overhand the sides, spray with baking spray and set aside.
2-In a small bowl, whisk with a: In a small bowl, whisk with a fork flour, brown sugar, salt, and cinnamon. Then add melted butter and whisk with a fork until coarse crumbs form, and place in the fridge until ready to use.
3-Using a mixer, beat softened cream cheese,: Using a mixer, beat softened cream cheese, sugar, and vanilla together until smooth, about 2 minutes. Add egg and mix just to combine.
4-In a medium bowl, whisk together flour,: In a medium bowl, whisk together flour, spices, baking powder, and salt.
5-In a large bowl, combine the pumpkin: In a large bowl, combine the pumpkin puree, sugar, brown sugar, oil, milk, eggs, and vanilla, and mix until smooth.
6-Gradually add the dry ingredients to the: Gradually add the dry ingredients to the pumpkin mixture, and whisk or stir until combined.
7-Spread pumpkin cake batter in prepared pan: Spread pumpkin cake batter in prepared pan. Using a spoon dallop cream cheese on top, but do not go all the way to the edges. Using the back of the spoon gently spread cream cheese mixture. Sprinkle the streusel crumb over the top and bake muffins for 45-55 minutes, or until a toothpick inserted in the middle comes out clean. If the top starts browning too much tent it with aluminum foil.
8-Stir powdered sugar, vanilla, salt and milk: Stir powdered sugar, vanilla, salt and milk. Start with 1 teaspoon of milk and gradually add more until desired consistency has reached. Drizzle over cooled cake and serve.
9-Store leftover in air-tight container for up: Store leftover in air-tight container for up to 1 week.