Chocolate Vanilla Spiral Cake

Ingredients:

Cupcake

• 3.5 cups of flour
• 1/2 tsp fine salt
• 2 tbsp. whole milk
• 4 tsp vanilla extract
• 8 large eggs, plus 2 yolks, at room temperature
• 450 g butter, room temperature
• 2.75 cups granulated sugar
• 1 cup dark cocoa powder

Glaze

• 1 cup powdered sugar
• 1-2 tbsp. whole milk
• Special equipment: a spiral baking pan with a hole in the middle (2.8 ml), 2 large zip-lock bags, and a long wooden skewer

Preparation:

1. Place a rack in the lower third of the oven and preheat to 180°C. Spray a spiral-shaped baking pan with a hole in the middle with cooking spray.
2. In a medium bowl, combine flour and salt. In another bowl, combine milk, vanilla, eggs, and yolks.
3. In a large bowl, beat the butter with a mixer on medium speed for 1 minute until smooth. Gradually add the granulated sugar, 1/4 cup at a time, and beat for about 5 minutes until light and fluffy.
4. Reduce speed to low and add the flour mixture, 1/4 cup at a time, beating for about 3 minutes, until well combined. Add the egg mixture and beat for another 3 minutes, until the dough is smooth.
5. Spoon 4 cups of batter into a large resealable plastic bag. Add cocoa powder to the bowl with the remaining batter and mix on low speed for 1 minute. Fill another large resealable bag with the chocolate batter.
6. Cut off the ends of the bags. Press strips of dough into the mold's cavities, alternating colors (the mold has an odd number of edges, so two strips of the same color will be next to each other). Use a wooden skewer to distribute the dough into the cavities, being careful not to spill dough of one color onto another. Press the remaining dough into the mold in large portions, alternating colors. Carefully smooth the surface with an offset spatula.
7. Bake for 55-60 minutes, until a skewer inserted into the center comes out clean and the top springs back when lightly pressed. Cool in the pan for 10 minutes. Invert onto a wire rack and let cool completely, about 2 hours.
8. For the glaze. Meanwhile, in a medium bowl, combine the powdered sugar and milk until you have a thick but pourable glaze—adjust the consistency by adding a little milk. Drizzle the glaze over the edges of the cake.