In a spacious bowl, combine the flours, instant yeast, granulated sugar, cocoa powder, and salt. Sift together to create a light mixture.

In a separate bowl, whisk together the eggs, vanilla, and milk. Slowly add this liquid blend into the dry ingredients, stirring gently until a velvety dough begins to form.

Drizzle in the neutral oil and knead the dough on a floured surface for about 10 minutes until smooth and elastic.

Place the kneaded dough in a lightly oiled bowl, cover with a damp cloth, and allow to rise in a warm spot for approximately 1 hour, or until doubled in size.

Punch down the risen dough, divide into equal portions, and shape each into a round bun.

Arrange them on a baking tray lined with parchment paper and let them rise again for about 30 minutes, covered lightly with a kitchen towel.

Preheat your oven to 350°F (175°C). Brush each bun with the egg wash and bake for 20-25 minutes or until golden brown.

While they cool, prepare the whipped cream by beating the heavy whipping cream, powdered sugar, and salt until soft peaks form.

Once cooled, slice the Chocolate Maritozzi open and fill generously with whipped cream.