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heart shaped cake in a to go box
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Lunchbox Cakes

Lunchbox cakes, also known as Bento or Korean lunchbox cakes, are happiness in a box. Dessert-lovers can find joy in the little things like these adorable little cakes. Decorated with dreamy embellishments, this eye-catching confection will surely sweeten up your day.
Course Dessert
Cuisine American
Prep Time 20 minutes
Cook Time 30 minutes
Decorating 1 hour
Total Time 1 hour 50 minutes
Servings 16 cakes
Calories 868kcal

Equipment

  • 1 3" heart shaped cutters
  • 1 cupler and pipng tips
  • 16 coated 6" cake boards
  • 16 to-go containers
  • cute parchment paper for lining the boxes

Ingredients

Doctored Strawberry Box Mix Cake

  • 1 box strawberry cake mix or white if you can't find strawberry
  • 1 cup all purpose flour (5 oz)
  • 1 cup granulated sugar (7 oz)
  • ¼ teaspoon salt
  • 1 cup sour cream (8 oz) room temperature
  • ½ cup melted unsalted butter (4 oz)
  • ½ cup milk
  • ¾ cup strawberry puree or preserves (6 oz) strawberry puree recipe
  • 3 large eggs
  • 1 teaspoon strawberry emulsion or extract I like amoretti or LorAnn oils
  • ½ teaspoon lemon extract

Easy Buttercream

  • 24 ounces powdered sugar sifted if not from a bag
  • 6 ounces pasteurized egg whites room temperature
  • 24 ounces unsalted butter room temperature
  • ½ teaspoon salt
  • 2 teaspoons vanilla extract
  • various gel food colors

Filling

  • 1 cup strawberry preserves or any filling you like

Instructions

Making A Strawberry Box Mix Cake

  • Place all of the ingredients into a mixing bowl and mix for 2 minutes on medium speed.
  • Pour the batter into 2 quarter sheet pans that have been prepared with cake goop, pan spray, or parchment paper. The size of your sheet pan may vary, so fill the sheet pan ½ way full. If you have leftover batter, you can freeze it or bake the remaining batter in a smaller cake pan. This recipe will make eight, 3.5” mini cakes, but it will depend on the size of the cutter and shape. 
  • Bake at 350ºF for 15-20 minutes or until a toothpick inserted comes out clean. 
  • Allow the cake to cool for 15 minutes in the pan.
  • Flip out the cake and wrap it in plastic wrap and freeze it until you are ready to start assembling your cake. If you are making your cakes ahead of time, keep them in the freezer for up to 2 months.

Making Easy Buttercream Frosting

  • Place the pasteurized egg whites and powdered sugar in the bowl of a stand mixer with the whisk attachment. Mix on low until combined and then bump up to high and whip for 3 minutes until it looks like royal icing. 
  • Add in your salt and then your butter in small pieces while mixing on low until combined, then bump up to high. Whip until light, white and fluffy and it doesn't taste like butter anymore. This can take 10-15 minutes.
  • Switch to the paddle attachment and mix on low for 15 minutes until it’s smooth and bubble-free (optional). 
  • Color your buttercream in as many colors as you like. I like ChefMaster gel food coloring over liquid for the best colors. 
  • Fill piping bags with the colored buttercream, using as many as necessary for your color palate. Pro-Tip: Use a coupler in each of your piping bags so that you can easily switch piping tips for different designs.  

Assembling the Lunchbox Cakes

  • Once your sheet cakes have chilled completely use your desired cutter (I used a 3” heart cutter) to cut out as many cakes as possible, about 16. Cold cakes are easier to cut, and handle and are less crumbly.
  • Set the cake on a small cake board so you can easily move it. 
  • Torte the little cake in half moving slowly with a serrated knife and turning the cake as you cut. You will have a thin cake layer, so handle it gently. (Optional)
  • Pipe a dam of buttercream around the edge of the cake.
  • Fill the center of the dam with a few Tablespoons of filling.
  • Place the next layer of cake on top. If your cakes are very soft and sliding, let them rest in the freezer for 15-30 minutes to firm up. 
  • With a small offset spatula, coat the exterior of the cake with your desired base color, then do a second layer of buttercream. Complete all of the buttercream coats before moving on to piping the edges and decor.
  • Practice your piping design briefly on a piece of parchment so you know you like it. It will be easier to scrape off the parchment than the cake! 
  • Now you can get creative and make these cakes as ornate or as simple as you like.
  • Finish your design with cute messages on top.
  • Once you are finished decorating all of your mini cakes, place them in the freezer to set. It will be much easier to move them without messing up the design if the buttercream is frozen.
  • Remove the cake from the cake board with an offset spatula or knife.
  • Place a sheet of parchment paper in a little to-go container, add the cake inside, and add a fork on top. 
  • If you are not serving these right away, wrap them in plastic wrap and keep them in the freezer until you are ready to package. Also, you could package them, wrap the box in plastic wrap and keep them in the freezer. They will keep up to 2 months in the freezer.

Nutrition

Serving: 1cake | Calories: 868kcal | Carbohydrates: 110g | Protein: 5g | Fat: 47g | Saturated Fat: 28g | Polyunsaturated Fat: 2g | Monounsaturated Fat: 12g | Trans Fat: 2g | Cholesterol: 151mg | Sodium: 396mg | Potassium: 93mg | Fiber: 1g | Sugar: 86g | Vitamin A: 1485IU | Vitamin C: 3mg | Calcium: 101mg | Iron: 1mg