Preheat the oven to 400 degrees F. It’s really important that the crust for this pie is par-baked. Start by rolling out your pie crust into a 13-inch (you can eyeball this) round. Fit in your nine-inch pie crust and trim the edges, leaving about a 1-inch overhang. Tuck under the overhang and crimp the edges the best you can. Make it look cute, if you want. Brush the edges of the pie crust with egg wash and stick it in the freezer for 15 to 20 minutes. Place the very cold pie tin on a baking sheet (this will make it easier to transport). Score the bed of the pie crust with a fork (this will help eliminate any puffiness that might happen when it’s in the oven).
Take a sheet of foil of parchment and spray it with cooking spray. Nestle the foil, cooking spray side down, into the pie crust. Pour in pie weights (or uncooked beans or rice) and transfer to the oven to bake for 15 minutes. At the 15-minute mark, remove the foil, and place back in the oven to bake for an additional 10 minutes. Remove the par-baked pie crust from the oven and set aside. Turn the heat down to 300 degrees F.
While the pie crust is par-baking, you can make the filling. In the bowl of a stand-up mixer, with the paddle attachment, add the butter and light brown sugar and white granulated sugar; beat until it’s light and fluffy and smooth, about 2 to 3 minutes. With the mixer going, pour in the brown rice syrup (or corn syrup) and molasses. Next, add the flour, salt, ground ginger, cinnamon, cloves and nutmeg. Then, add the eggs, one at a time, making sure each one is incorporated before moving onto the next one. Lastly pour in the vanilla and heavy cream.
Give one last mix and pour it in the par-baked pie crust. Carefully transfer it to the oven and bake for 45-50 minutes. The top will appear cracked and puffy. Remove it from the oven and allow it to cool completely, around 2 to 3 hours. During this time, it will set and deflate. Slice it up and serve it with whipped cream.