Red Velvet & Raspberry Supreme Cake
Super-moist and decadent red velvet cake filled with pink whipped vanilla cream with raspberries, creamy marshmallow cream cheese filling and smothered in a satiny and fluffy chocolate frosting topped with more fresh raspberries.
Ingredients
For the Cake:
  • 3/4 cup 170 g unsalted butter, at room temperature
  • 1 cup 225 g packed light brown sugar
  • 1 cup 200 g white sugar
  • 3 tablespoons 45 ml *red velvet flavor
  • 1 teaspoon super red soft gel paste optional
  • 3 eggs at room temperature
  • 2 cups 260 g all-purpose flour
  • 1/2 cup 55 g cake flour
  • 1 tablespoon 8 g Dutch-process cocoa powder
  • 1 teaspoon 8 g kosher salt
  • 1-1/2 cups 360 ml buttermilk, warm
  • 1/4 cup 60 ml mayonnaise
  • 1 tablespoon 15 ml vinegar
  • 1-1/4 teaspoons 8 g baking soda
For the Marshmallow Cream Cheese Filling:
  • 1/2 cup 63 g icing sugar (confectioners' or powdered), sifted
  • 1/2 cup butter 115 g, at room temperature
  • 1/4 cup 57 g cream cheese, softened
  • 1/2 teaspoon 2.5 mL pure vanilla extract
  • 1/2 jar 106 g marshmallow cream (such as Marshmallow Fluff)
  • A pinch of salt
For the Pink Whipped Vanilla Cream Filling:
  • 2 tablespoons 30 ml cold water
  • 1-1/2 teaspoons unflavoured gelatin such as Knox brand
  • 1-3/4 cups 420 ml whipping cream (35-37% fat), cold, divided
  • 1/2 cup 63 g icing sugar
  • 1 teaspoon 5 ml pure vanilla extract
  • A pinch of salt
  • A drop or two of red or pink gel paste
For the Chocolate Frosting
  • 2 cups 454 g(4 sticks) unsalted butter, at room temperature
  • 4 cups 500 g icing sugar sifted
  • 1 tablespoon 15 mL pure vanilla extract
  • Pinch of salt
  • 8 oz 250 g quality dark or extra dark chocolate, chopped, melted and slightly cooled
  • 1/2 cup 120 ml whipping cream (35-37% fat)
  • 2 cups fresh raspberries washed and dried
Instructions
For the Cake:
  1. Preheat oven to 350° F. Butter the bottom of three 8-inch round cake pans, line with parchment rounds, and dust with flour, tapping out the excess.
  2. In a stand mixer fitted with the paddle attachment, beat the butter, sugars, red velvet flavor, and red gel paste on medium-high speed until lighter in color and slightly increased in volume, about 5 minutes. Lower the speed to medium and add the eggs, one at a time, mixing until each is fully incorporated before adding the next.
  3. Sift the flour and cocoa powder into a medium bowl. Add the salt to the dry ingredients after sifting, and whisk dry ingredients. Alternate dry ingredients and buttermilk into creamed mixture, beginning and ending with dry ingredients. Mix until just incorporated, or finish by hand gently. Fold in mayonnaise.
  4. In a small cup or bowl, combine the vinegar and baking soda until it fizzes, then quickly add the batter and whisk until blended.
  5. Divide the batter evenly between the prepared pans. If possible, weigh the batter in each cake pan for 460 g each (excluding the pans--you will want to tare the scale each time.) This ensures even layers. Smooth with small offset palette knife, and bake on top of a baking sheet (two pans on sheet for first round, then the final pan) until a toothpick inserted in the center comes out clean, about 25 minutes. Try not to over-bake.
  6. Let pans cool on wire rack for 20 minutes, then invert cakes onto racks, gently, peeling away parchment rounds. Let cool completely.
For the Marshmallow Cream Cheese Frosting:
  1. In an electric mixer fitted with paddle attachment, combine butter and icing sugar on low until blended, about 1 minute. Add vanilla and salt and mix on medium speed for about 3 minutes.
  2. Add marshmallow cream and cream cheese and beat until combined and creamy, about 1 minute.
For the Pink Whipped Vanilla Cream Filling:
  1. In a small bowl, place the cold water and sprinkle with the gelatin. Let sit for at least 10 minutes. In a small saucepan, bring 1/2 cup of the cream just to a simmer, then stir into the gelatin mixture. Refrigerate, stirring frequently, until cool but not set, about 8 minutes.
  2. In a chilled stainless steel bowl, beat the remaining whipping cream, icing sugar, vanillla and salt until it thickens slightly and soft peaks form. Slowly add the gelatin mixture and food colouring and continue beating until medium-firm peaks form (should be thick enough to spread). Keep covered and chilled until ready to use.
For the Chocolate Frosting:
  1. In a bowl of stand mixer fitted with paddle attachment, combine the icing sugar and butter and beat on low speed for about 1 minute. Add vanilla and salt, and beat on low until well combined. Add the melted chocolate and beat on medium speed until smooth (about 2 minutes). Add whipping cream and beat on med-high speed for another minute.
Assembly of the Red Velvet & Raspberry Supreme Cake:
  1. On an 8"inch round cake board (or cake plate), put a small dollop of frosting.
For a 3-layer cake (3 cake layers + 2 layers of filling):
  1. Place your first layer face-up on the board (or plate) and spread the Marshmallow Cream Cheese Frosting, leaving about 1/2" around the edge, using an offset palette knife. Place the second cake layer face-up and repeat with a thick layer of Pink Whipped Vanilla Cream Filling. Gently press a layer of fresh raspberries into the filling, slightly spaced apart. Top with another thick layer of the Pink Whipped Vanilla Cream Filling and spread evenly using your offset palette knife.
  2. Place your third cake layer atop the pink filling, face-down. Gently adjust the cake so that it is straight and lined up properly. Cover with plastic wrap and refrigerate for about 30 minutes.
  3. Stir the Chocolate Frosting well with a rubber spatula to remove air bubbles, and then frost the entire outside of the cake until you have a smooth layer, sealing in all crumbs. Refrigerate until the frosting firms up, about 30 minutes. Repeat with thick and even layer of the frosting, adding some swirls or patterns using a large spatula. Top with fresh raspberries and a sprinkling of icing sugar, if desired.
  4. Keep refrigerated (this cake will stay moist!) but serve at room temperature.
For the 6-layer version:
  1. Cut your 3 cake layers each once horizontally with a long, serrated knife, so you have a total of 6 layers (layers will be thin).
  2. On an 8"inch round cake board (or cake plate), put a small dollop of chocolate frosting. Place your first layer face-up on the board (or plate) and cover with 1/6 of the Pink Whipped Vanilla Cream Filling, leaving about 1/2" clearance around the edge. Gently press a layer of fresh raspberries into the filling, and then cover with another 1/6th of the filling, spreading until even. Place another cake layer face-up and cover with 1/2 of the Marshmallow Cream Cheese Frosting, spreading until even.
  3. Repeat until you come to your final layer, which you will place face-down. If you find the cake too soft and unstable, put in refrigerator for a few moments to firm it up, then resume.
  4. Cover the entire cake gently with plastic wrap, and then, once covered, use your hands to carefully ensure the cake is lined up straight. Chill for at least 30 minutes.
  5. Stir the Chocolate Frosting well with a rubber spatula to remove air bubbles, and then frost the entire outside of the cake until you have a smooth layer, sealing in all crumbs. Refrigerate until the frosting firms up, at least 30 minutes. Repeat with thick and even layer of the frosting, adding some swirls or patterns using a large spatula. Top with fresh raspberries and a sprinkling of icing sugar, if desired
Sweetapolita's Notes

I have recently started using Lorann Red Velvet Flavor, which gives the cake its dark, red colour and just slightly-citrus taste that doesn't fade once the cake is baked. If you can't get this ingredient, you can replace with 1 oz of red liquid food colouring, or 1-2 tablespoons of a super red gel paste colour along with 1 tablespoon of pure vanilla extract.

[whipped cream filling adapted from Bon Appetit Desserts]