Preheat oven to 350° and line a 13x9 pan with parchment paper and spray with nonstick spray.
Grate carrots and set aside.
In a medium bowl, combine cream cheese and sugar and mix until smooth. Add in egg and vanilla and stir until no lumps remain. I find the best way to do this is with a whisk or hand mixer. Set aside.
In a large bowl (or pie plate) combine the crumb topping ingredients- butter, brown sugar, flour, salt, and cinnamon. Mix with clean hands until combined. Set aside.
In a small bowl, mix flour, baking powder, salt, cinnamon, and pumpkin pie spice. Set aside.
In a large bowl, cream butter and sugars together until completely smooth.
Add in eggs and vanilla and mix well.
Alternate adding the dry mixture with the buttermilk until all is added and incorporated. Fold in carrots and coconut. Pour into prepared pan.
Gently spread cream cheese mixture on top.
Sprinkle crumb mixture on top of cream cheese mixture.
Bake for 55-65 min or until toothpick comes out with just a few moist crumbs.
Let completely cool and top with glaze.
Can be kept at room temperature for 3-4 days.
Best served 1-2 days after making.