in large mixing bowl whisk together cocoa powder and baking soda. Carefully pour in boiling water and whisk until well blended; allow to cool for 5 minutes.
Meanwhile, in another large mixing bowl add the melted butter, vegetable oil, sugar, vanilla and salt and beat until well combined.
Stir in eggs and egg yolks, mixing after each addition, just until combined. Blend in cocoa mixture and then blend in heavy cream…
