To Make the Cake:

1. Set oven to a true 325°. An oven thermometer will help you determine whether your oven is actually the correct temperature. 
2. Sift together 187 g all-purpose flour, ½ tsp baking soda, natural cocoa powder, dry pudding mix, and ½ tsp kosher salt into a medium bowl. Set aside. 
3. Sift together 127 g all-purpose flour, ¼ tsp baking soda, and ⅓ tsp kosher salt in a second bowl. Set aside.
4. Place 153 g of sour cream in a small bowl and set aside, next to the dry ingredients for the chocolate cake.
5. Place 74 g of sour cream and a tablespoon of neutral oil in a second small bowl. Set aside, next to the dry ingredients for the vanilla cake.
6. This step is very important! For this recipe, you’ll need two mixing bowls. Your primary mixing bowl, where you’ll make your chocolate cake batter, and your secondary mixing bowl, where you’ll make your vanilla cake batter. Before you start (in your primary bowl), you need the bowl weight of each bowl. Write down the bowl weight for each bowl and set that aside where you’ll be able to find it quickly later.
7. Place all of the butter into your primary mixing bowl. Mix on medium speed until the butter is completely smooth.
8. Add the granulated sugar and cream the mixture until light and fluffy. (psst…don’t know what it means to “cream until light and fluffy”? Take a look at this article!) Scrape the sides and bottom of the bowl as necessary to ensure even mixing.
9. Add all six eggs, one at a time. Mix each egg until it’s fully incorporated before adding the next egg. Scrape the sides and bottom of the bowl as necessary to ensure even mixing.
10. Add all of the pure vanilla extract and mix until fully combined.
11. Place ⅓ of the batter into a second mixing bowl. To do this, follow these steps: a) Weigh the primary mixing bowl while it is full with all of the batter; subtract the weight of the empty mixing bowl, using your note from earlier; and c) multiply the remaining weight by .33 to figure out how much batter needs to be added to the second bowl. Then, remove that amount of batter from the primary mixing bowl into the second mixing bowl. 
12. To finish the chocolate batter: Add half of the flour/cocoa mixture and mix on low speed until nearly combined. Scrape the sides and bottom of the bowl as necessary.
13. Add all of the plain sour cream (not the sour cream/oil mix) and mix on low speed until nearly combined.
14. Add the second half of the flour/cocoa mixture and mix on low speed until nearly combined. Scrape the sides and bottom of the bowl with a stiff spatula, and fold the batter until it is smooth and combined. Set the chocolate cake batter aside while you prepare the vanilla cake batter.
15. To finish the vanilla batter: Add half of the flour mixture and mix on low speed until nearly combined. Scrape the sides and bottom of the bowl as necessary.
16. Add all of the sour cream/oil mix and mix on low speed until nearly combined.
17. Add the second half of the flour mixture and mix on low speed until nearly combined. Scrape the sides and bottom of the bowl with a stiff spatula, and fold the batter until it is smooth and combined. 
18. Prepare a 10- or 12-cup bundt pan as you normally would. Use an ice cream scoop to layer chocolate and vanilla batter in the bundt; you should begin and end with chocolate batter, since there is more chocolate than vanilla.  My daughter says that you should not swirl the mixture with a skewer or the back of a spoon, but I say do what you like (just don’t tell her I said that). 
19. Bake at 325° for 65-75 minutes, or until the internal temperature of the cake reaches 212°F.
20. Remove the pan from the oven. After ten minutes, remove the cake from the pan by inverting the pan onto a cooling rack. Allow to cool completely.

To Make the Vanilla Simple Syrup:

1. Place granulated sugar, water, and salt in a small saucepan. Bring to a boil.
2. Remove from the heat and add pure vanilla extract. Stir to combine.
3. Once the cake is fully cooled, brush with the fully cooled simple syrup.

To Make the Vanilla 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.  Add the fine sea salt, cream of tartar, and vanilla extract. 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. Top with crumbled graham crackers and enjoy!