To Make Sweet Potato Puree:

1. Peel and rinse sweet potatoes.  Dice into 1/2-inch cubes.  Place in a medium saucepan and fill the saucepan with enough water to completely cover the potatoes.
2. Bring the potatoes to a boil, then reduce to a low boil for 12 minutes.  When potatoes are fork tender, remove from the heat and smash with a potato ricer or potato masher.  Set potatoes aside for about 45 minutes to cool to room temperature.
3. Measure 425 grams (2 c) of sweet potatoes in a small bowl and set aside.

To Make the Batter:

1. Set your oven to a true 325°F.  An oven thermometer is extremely useful here, since most ovens will not reach 325°F when set to 325°F.  
2. Sift together the all-purpose flour, cinnamon, nutmeg, kosher salt and baking soda in a medium bowl.  Set aside.
3. Add the room-temperature butter to the bowl of your stand mixer or a large mixing bowl.  Mix just the butter with your hand or stand mixer until the butter is completely smooth.  Add the brown sugar and cream until the mixture is light and fluffy.
4. Add the eggs, one at a time, mixing each egg until it is completely incorporated into the mixture.  Scrape the sides and bowl as needed to ensure even mixing.
5. Add the vanilla and mix thoroughly.
6. Add half of the flour mixture and mix until just combined.
7. Add all of the sweet potato puree and mix until just combined.
8. Add the second half of the flour mixture and mix until just combined.  Using a rubber spatula, give the sides and bottom of the bowl a final scrape to ensure that the batter is even mixed.
9. Prep a 10- or 12-cup bundt pan as you normally would (I use butter and flour to prep pans for this cake) and add the batter to the pan.  Use a rubber spatula to even out the batter, then tap the pan on the countertop several times to remove air bubbles from the batter.
10. Bake for 55-70 minutes in a true 325°F oven, or until an instant-read thermometer reads 212°F-215°F.  

To Make the Simple Syrup:

1. Add sugar and water to a small saucepan.  Bring to a boil and reduce to a simmer.  Remove from the heat as soon as the sugar is completely dissolved.
2. Add pure vanilla extract and bourbon and stir to combine.
3. Allow the cake to cool in its pan for ten minutes, then invert and place on top of a cooling rack.  Brush simple syrup on the cake and allow to cool completely.

To Make the Meringue:

1. Bring 2” of water to a low boil in a large (3 qt.) saucepan.  
2. Carefully separate eggs, placing them In a clean metal bowl (either a stand mixer or a large stainless steel bowl).  Add sugar and stir to combine.
3. Place a metal bowl over the top of the saucepan while the water is still boiling.  Whisk the egg white mixture over the saucepan until all of the sugar is completely dissolved.  
4. Remove the metal bowl from the stove.  Using the whisk attachment on either your hand mixer or your stand mixer, whisk the mixture on the lowest speed until it is nearly opaque.  
5. Increase the mixer to medium speed until the mixture begins to look light and fluffy.
6. Increase the mixer to the highest speed until the meringue is done.  To check the meringue, remove the whisk attachment from the mixture and invert it.  If the meringue slowly folds down over the whisk attachment, it’s complete.
7. Using an offset spatula, quickly spread the meringue over the cooled cake.  If desired, use a butane torch to toast the meringue.