How to Make It
Preheat oven to 350 °. Grease and flour a 10-inch springform pan.
To make the streusel, whisk together the brown sugar, flour, cinnamon, and salt in a medium-sized mixing bowl. Cut in butter using fingertips until small clumps form. Stir in pecans. Set aside in fridge until ready to use.
To make the filling, whisk together the pumpkin, sugar, pumpkin pie spice, and egg in a medium bowl until combined. Set aside.
To make the cake, beat the butter and sugar in the bowl of a stand mixer fitted with a paddle attachment at medium speed until pale an fluffy, 4-5 minutes. Beat in the eggs, 1 at a time, and vanilla extract.
Whisk together the flour, baking powder, baking soda, and salt in a medium bowl. Slowly mix the flour mixture into the butter mixtures until barely combined. Mix in the sour cream and pumpkin.
Spread ½ of the cake batter into prepared pan. Gently spread pumpkin filling over cake batter in pan; sprinkle evenly with about half of the streusel. Top with remaining cake batter; sprinkle evenly with remaining streusel. Bake at 350 ° for 45-50 minutes or until wooden skewer inserted into the center of the cake comes out clean. Cool in pan 15-20 minutes. Run a knife around the edge of the cake to loosen from the sides of the pan; remove sides.
To make the glaze, whisk together confectioners sugar, maple syrup, and 3 tablespoons cream. Whisk in remaining tablespoon of cream, 1 teaspoon at a time, until desired consistency is reached. Drizzle over cake and serve.