Preheat oven to 350 degrees and line a 12-cup cupcake pan with nonstick cooking spray.
In a large bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt until well combined. Set aside.
In a medium bowl, whisk the eggs, granulated sugar, brown sugar, oil, and vanilla together until well combined and smooth.
Pour half of the wet ingredients into the large bowl with the dry ingredients, then pour in half of the buttermilk and mix gently for a few seconds, without over-mixing.
Add the rest of the wet mixture to the bowl, then the rest of the buttermilk, and finally, the chocolate chips. Whisk gently for a just few seconds again. (The batter will be thin.)
Spoon the batter *Halfway* into the cupcake tins. Filling more than halfway will cause them to overflow and/or sink!! This step is crucial!
Bake for 18-21 minutes. They are done when an inserted toothpick comes out clean.
Remove them from the oven and allow them to *completely cool* on a cooling rack before you proceed with adding the cream filling.
Cream Filling:
Combine all of the cream filling ingredients in a large bowl and use an electronic mixture to combine. The mixture will seem crumbly at first, use rubber spatula to finish mixing until it comes together.
Take each cupcake and carefully slice the top of each one off with a knife. Use a small cookie scoop and place a heaping spoonful of cream filling in the middle of each cupcake.
Place the cupcake top over the cream and push down gently to spread the cream around the top. Repeat for each cupcake, and prepare to be amazed.