After sharing this easy lemon buttercream floral sheet cake over on Instagram, you all asked for a more detailed post here! To speed up this recipe, I used two box cake mixes but added lemon extract and zest to really make it vibrant! I hope you love this dessert idea for an Easter dinner, bridal or baby shower, or spring/summer gathering. If the frosting bouquets feel overwhelming, try just adding one stem per square!
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Frosting Bouquet:
I didn’t want to cut into this sheet cake until we were ready to serve it. For decorating, I used a piece of floss (thread works, too!) to mark even squares on the cake. I then used different colors of “glaze” (see recipe section) to make the floral bouquet. These are my favorite food color gels.
I clipped a VERY small tip off of each piping bag end, and on just the pink florals used a drop flower 224 Wilton frosting tip. The rest is just lines and dots! I’ll share a few floral tip favorites below!
Easy Lemon Buttercream Floral Sheet Cake
Box cake mixes with lemon extract and zest. Finished with a detailed floral bouquet for each square!
Ingredients
- 2 Box Vanilla Cake mix Betty Crocker
- 1 Tablespoon Lemon Extract (NOT JUICE)
- Zest of one lemon
Lemon Buttercream Frosting
- 1 Cup (2 sticks) Room temperature butter
- 4 Cups Powdered sugar
- 2 teaspoons Lemon extract
- 4-5 Tablespoons Heavy cream Milk is okay, too
- pinch of salt
- I used a few drops of purple coloring
Frosting glaze for floral bouquet
- 3 1/4 Cup Powdered sugar
- 4 1/2 Tablespoons Milk
- 1 Teaspoon Lemon or vanilla Extract
Instructions
- Prepare 2 box cake mixes per directions. Prepare a baking sheet around 13×17 with non-stick spray.Preheat oven to temp on cake mix box (usually 350°)Pour cake batter into tray filling about 3/4 full. DO NOT overfill or the cake will rise too high and may spill over. I had a little batter left so I made 3 cupcakes OR you can discard remaining batter.Bake about 27-30 minutes or until toothpick comes out of the center clean.Allow cake to fully cool and then chill before frosting. I like to make mine a day ahead if possible. Cooling will allow the cake to settle a bit.Frost cake with buttercream being careful to spread without picking up the crumb and spreading into the frosting. Use a large knife or icing spatula to spread it as flat as possible. Frosting on a cooled cake makes this much easier!Use a thread or floss to mark even squares. This will help guide you for where to place your florals.Whisk together powdered sugar, milk and extract. The floral glaze should be thick but still run smooth without breaking when you lift the spoon/whisk up. When you lift the spoon it will run in a steady flow back to the bowl but it will slightly keep its shape before dissolving back in. If it is too runny, it will not hold any shape as it runs back into the bowl. Test a little bit of your glaze on a plate to make sure it's not too runny or too thick.Mix a couple of batches of the floral frosting glaze if you're doing a full bouquet. If you're just doing one floral per square, one batch is plenty. Use food gels to color frosting in individual cups or bowls. Add glaze to piping or gallon ziplock bags and cut a very small tip off the end for fine detailing.Pipe 3-4 stems on each square curving them so the lines at the bottom come together where a "ribbon" will be. Add florals of your choice for each stem. See tips and FAQ's below for helpful ideas!
Notes
If you’re making a smaller 9×13 cake, just use one box mix and add 2 teaspoons lemon extract instead of a tablespoon to the batter.
Tips for making Easy Lemon Buttercream Floral Sheet Cake
- Use box cake to speed up this recipe!
- Fill the pan only 3/4 full because the cake will rise. Discard or make 3-4 cupcakes with excess batter.
- Cool and chill cake a few hours or overnight before decorating. This will make it easier!
- Use an icing spatula to spread the first layer of frosting really smooth and flat.
- Use floss or thread to create light lines to mark the squares on the cake. This way you don’t have to cut it until you serve it.
- To make things easier on yourself and break up the decorating part, baking the cake and preparing the frosting the day before would help a lot.
- Chill cake after frosting. It’s delicious served cold.
FAQ’s about Easy Lemon Buttercream Floral Sheet Cake:
- Can this cake be made ahead and frozen? YES! It can be frozen after baked and cooled and even after being frosted. Be sure to gently but fully cover the cake and sides with plastic wrap. I wouldn’t recommend freezing for more than a few days so it’s still very fresh.
- How can I make the frosting bouquet if I have never done florals before? I started by marking the squares on the cake and then taking the green frosting and making 3 curved lines that met at one spot. You can always add more branches once you start adding florals.
- If you’re not sure what floral pattern you’d like to do, I like to draw them out on a paper first to create a sort of guide for myself! They don’t have to be perfect and they don’t even have to be a real flower! Just have fun and let creativity lead you.
- If doing a full bouquet feels overwhelming or too time consuming, just add one stem of lavender or one group of flowers to each piece. That will still be gorgeous! Another option would be to simply decorate the 4 corners of the cake with florals.
- Other spring cake variations and ideas: Vanilla sheet cake with strawberry frosting and frosting strawberries on each square. Carrot sheet cake with a single tiny carrot piped on each slice. Vanilla sheet cake with purple frosting and light, medium and dark purple lilacs piped on each square. Lemon sheet cake with light yellow frosting and frosted sunflowers or little lemons!
Other spring desserts you might enjoy:
Thank you so much for stopping by today! I hope you feel inspired by this dessert idea. I would love to hear from you if you decide to make it or your own variation. Happy baking, sweet friend!