Preheat oven to 350°F (175°C).
Spray a 9” springform pan with nonstick spray and line bottom with parchment paper.
In a large bowl, beat shortening + granulated sugar with a mixer on high speed for 3 minutes until fluffy.
Add eggs, sweet potato, sour cream, molasses, and vanilla; mix until smooth.
In another bowl, whisk together flour, baking powder, baking soda, salt, and cinnamon.
Add dry ingredients to wet mixture and mix until just combined (do not overmix).
In a small bowl, beat cream cheese + powdered sugar until smooth.
In a medium bowl, combine flour, cinnamon, brown sugar, and pecans.
Cut in shortening with a fork until mixture is crumbly.
Spread half the batter in the prepared pan.
Spread cream cheese mixture evenly over batter.
Sprinkle with half the streusel.
Add the remaining batter, then top with the rest of the streusel.
Bake for 55–65 minutes, or until a toothpick inserted in the center comes out clean.
Cool completely in the pan on a wire rack.
In a small bowl, whisk together powdered sugar, molasses, and milk until smooth.
Drizzle over cooled cake before serving.
