Go Back
–+ servings
Carrot cake sheet cake decorated with piped cream cheese buttercream flowers and carrots for Easter.

High Altitude Carrot Cake Sheet Cake with Buttercream Flowers for Easter

Heather Smoke
This moist carrot cake sheet cake is full of warm spices, frosted with the best cream cheese buttercream that's piped in a gorgeous floral arrangement, complete with little carrots.

All recipes on Curly Girl Kitchen are developed for high altitude at 5,280 feet. See FAQs for adjusting to higher or lower elevations.

5 from 1 vote
Print Recipe Pin Recipe
Prep Time 1 hour 50 minutes
Cook Time 40 minutes
Total Time 2 hours 30 minutes
Course Dessert
Cuisine American
Servings15 (15-20)

Equipment

  • Stand Mixer with Paddle Attachment
  • 9x13 Baking Dish
  • Parchment Paper
  • 12-Inch Disposable Piping Bags + Couplers
  • Piping Tips, (1M, 125, 104, 352, 101, 61, 123)

Ingredients
 

Cake

  • ¾ cup unsalted butter
  • 2 cups (9oz) peeled and finely grated carrots
  • ½ cup unsweetened applesauce
  • ½ cup vegetable oil
  • 1 cup whole milk, room temperature
  • 2 tsp apple cider vinegar or white distilled vinegar
  • 1 cup granulated sugar
  • 1 cup light or dark brown sugar, lightly packed
  • 4 large eggs, room temperature
  • 2 tsp vanilla extract
  • 3 ¼ cups all-purpose flour, fluffed, spooned and leveled
  • ½ tsp baking soda
  • 2 tsp baking powder
  • ½ tsp coarse Kosher salt (if using table salt, use half the amount)
  • 2 tsp ground cinnamon
  • 1 tsp ground ginger
  • ½ tsp ground cloves
  • ½ tsp ground nutmeg
  • ½ cup finely chopped walnuts, optional

Buttercream

  • 12 oz (1 1/2 blocks) full fat cream cheese, cold
  • ¾ cup unsalted butter, softened to room temperature
  • ¾ cup vegetable shortening
  • 7 ½ - 8 cups powdered sugar
  • 2 tbsp corn starch
  • 1 tbsp meringue powder (optional)
  • ¼ tsp coarse Kosher salt (if using table salt, use half the amount)
  • 1 tbsp vanilla extract
  • gel food coloring
  • sugar pearls and nonpareils

Instructions
 

Bake the Cake

  • Preheat the oven to 350 F, and position a rack in the center of the oven. Line a 9x13 inch baking sheet with parchment paper, and spray the paper with non stick baking spray. Since this is a large cake, the paper will help to ensure the cake comes out cleanly, if you'll be turning it out onto a serving board or platter to frost and decorate it.
    Note: If you plan to frost and serve the cake directly in the baking pan, then there's no need to line it with parchment paper. Simply spray the pan with non stick baking spray or grease it with butter and flour.
  • Melt the butter in a saucepan over medium low heat.  Continue cooking, swirling occasionally, until nutty brown solids form on the bottom of the pan.  Immediately scrape the butter and the browned bits into a large mixing bowl and let cool for 5 minutes.
  • Add the grated carrots, applesauce, oil, milk, vinegar, granulated sugar, brown sugar, eggs and vanilla to the brown butter, and whisk until smooth.
  • In a separate bowl, sift together the flour, baking soda, baking powder, salt and spices.
  • Add the dry ingredients to the wet, and whisk for 10-15 seconds until combined. If adding the walnuts, fold them in now.
  • Pour the batter into the prepared pan, and bake for about 40 minutes, until the top of the cake springs back when gently touched and a toothpick inserted in the center comes out clean.
  • Set the pan on a cooling rack and cool completely, covered with a clean kitchen towel.

Make the Buttercream

  • In the bowl of your stand mixer fitted with the paddle attachment, beat the cream cheese, butter and shortening for 1-2 minutes until smooth.
  • In a separate bowl, combine the powdered sugar, corn starch, meringue powder and salt. With the mixer on low, add the powdered sugar mixture by spoonfuls, then add the vanilla.
  • Whip for 4-5 minutes on medium speed until light and fluffy, scraping the bowl down occasionally. Add a little more powdered sugar if the buttercream is too soft, or 1-2 tablespoons milk or cream if it's too thick. Turn the speed down to "stir" and mix for 1 more minute. Keep the buttercream covered until ready to use, so the surface doesn't crust over.

Crumb Coat the Cake

  • Before decorating your cake with the piped flowers, you'll need to prep it with a thin crumb coat of frosting.
  • Flip the cake over onto a serving board or platter, and peel off the parchment paper.
  • Use an icing spatula to frost the cake all over with a thin layer of the frosting. Smooth out the sides of the cake with a bench scraper. If you like, you can smooth out the top edges, too, but I like to leave a rough edge of buttercream there, sort of like a "frame" for the design inside.

Color the Buttercream

  • Decide on your color palette. I chose shades of pink, white, yellow and orange, with a small amount of green for the leaves or carrot tops. Your flowers will look prettiest and the most realistic with various colors blended and swirled together.
  • Divide your buttercream between several bowls, so you can color each separately. These are the colors that I used (the number of drops of food coloring that you'll need will change depending on how much of the buttercream you're coloring).
    Pale Pink: 1 drop "electric pink"
    Medium Pink: 2-3 drops "electric pink"
    Dark Pink: 1 drop "super red"
    Green: a few drops each of "electric green" and "leaf green" with a tiny drop of "super black" (you only need about 1/4 cup of green buttercream, just enough for a few leaves)
    White: nothing, unless your buttercream has a yellowish tint, you can add some "bright white" or a small drop of "violet" to neutralize the yellow
    Yellow: 2 drops "lemon yellow" and 1 small drop "warm brown"
    Orange: 2 drops "orange" and 1 small drop "warm brown"

Prep the Piping Bags

  • Since this design uses so many different colors and different piping tips, I recommend using a "double bag" method. Basically this means you will have your buttercream in piping bags with the tips snipped off, rather than fitted with couplers or piping tips.
    Then, you'll have two empty piping bags, one fitted with a standard sized coupler (for changing out smaller piping tips), and the other one fitted with a larger coupler, or just a larger piping tip. By using this method, you can drop the bags filled with buttercream into the empty bags fitted with tips, and freely move all the colors between large and small piping tips as needed.
    I highly recommend reading this post: How to Use Piping Bags, Piping Tips and Couplers.
  • Divide the buttercream between your piping bags. I suggest combining 2-3 colors in some of the bags, for more variation in your piped flowers.

Piping the Flowers

  • You can pipe many of the flowers directly onto the cake, such as rosettes, drop flowers, swirls, stars and shells, and any number of other flowers using tips from your piping tips set.
    But for flowers that need each petal piped individually (like peonies, tulips or traditional roses) you'll need to do these on a flower "nail". You'll need to prep the flower nail by spreading a dot of buttercream on the nail, then sticking a small square of parchment paper or wax paper onto the buttercream. Then you can pipe your flower onto the paper. When the flower is done, simply slide the paper off the nail, and place the paper with the flower on something flat, like a cutting board. Stick a new piece of paper onto the nail to pipe the next flower. When all your flowers are done, place the cutting board in the freezer for 10 minutes. Then you can use a small offset spatula to slide the cold buttercream flowers off the paper and place them on your cake.
  • I started by piping a few large peonies, using my curved petal tip (121 or 123). For smaller peonies, you can use a smaller curved petal tip (61). Then I piped a few traditional roses (125 for large, 101 or 103 for small). After chilling these in the freezer, these flowers are the first ones I arranged on my cake.
  • Use tip 1M to pipe large, medium and small rosettes.
  • Use tip 1M to pipe some drop flowers. Don't go too crazy with these right now - you can fill in the cake with more at the end.
  • Use tip 104 to pipe some squiggly ruffles. These might look a little strange at this point, but when the cake is done, and they're peeking through all the flowers, they look really pretty.
  • Use tip 1M to pipe some shells or swoops. (At this point, I also meant to pipe some large star shapes with tip 4B or 6B, but I forgot to add them.)
  • The cake should be almost full by now, so just finish filling it in with anything you like. Go nuts with more drop flowers, stars, or anything else you feel like filling in the gaps with.
  • Use tip 101 to pipe the carrots, keeping the wider side of the tip against the cake with the narrow side facing up.
  • Use tip 352 to pipe some leaves or carrot tops.
  • For a final touch, place a few large sugar pearls and scatter some nonpareils. Don't sprinkle the nonpareils everywhere - just pinch them between your fingers and strategically sprinkle them here and there to add more visual interest and depth. Your cake is done!

Notes

Cake Notes:
  • Leftover cake with frosting should be kept refrigerated, in an airtight container or cake carrier, for up to 3 days.  Bring the cake to room temperature before serving.
  • You can bake the cake one day in advance, before decorating. When the cake has cooled to warm, cover the pan tightly with plastic wrap and keep at room temperature until ready to decorate.
Buttercream Notes:
  • I deliberately made this a thicker buttercream, so all the piped flowers can hold their shape.
  • The shortening helps to stabilize the cream cheese, so that the frosting isn't too soft.  This is especially helpful in warmer climates.  If you prefer, you can use the same amount of butter to replace the shortening, but your frosting will be a little softer and less stable.
  • This is a "crusting buttercream", which will dry to the touch after being applied to the cake, but stay soft underneath the surface.
  • This makes a lot of buttercream, which you'll need for all the piping. If you're not planning on piping flowers, and you want to frost your cake with a simple coat of frosting, you should cut the buttercream recipe in half, use butter instead of shortening, and leave out the corn starch.  You could also use less powdered sugar if you want a creamier, softer, less sweet frosting.
Keyword Brown Butter, Buttercream Flowers, Carrot Cake, Cream Cheese Frosting, Easter, High Altitude
Tried this recipe?Let us know how it was!
https://curlygirlkitchen.com/