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Bright Lemon Sheet Cake with creamy lemon buttercream frosting is a sunny dessert perfect for feeding a crowd!

Of all the Lemon Cakes I have recipes for, this Lemon Sheet Cake just might be the easiest of them all! It’s moist just like our Lemon Buttermilk Cake and has a delicious frosting like our Lemon Bundt Cake.

Moist Lemon sheet Cake served on a white plate.

a lemony dessert for spring & summer

Spring makes me think of fruit and lemons and the dessert we are sharing today – Lemon Sheet Cake!

This Lemon Pudding Cake with Lemon Frosting is one of the easiest Lemon Cake Recipes you will ever make! It’s similar to our Chocolate Sheet Cake, kind of a Lemon Texas Sheet Cake!

We started with a lemon cake mix from a box – so simple! It also has a pudding mix in it, which makes it so good. Because of the added pudding and buttermilk mixture, the texture will be more dense and moist than a regular cake, and a bit fudgy like a brownie.

The best part is the lemon buttercream frosting on top. This Lemon Sheet Cake Recipe is SO delicious and creamy!!

The lemon flavor is a perfect dessert for Spring and Summer!!

Pudding boxes and cake mix boxes for lemon sheet cake.

Lemon cake from a mix

The reason this is an EASY Lemon Cake is that it’s not made totally from scratch.

You actually use a box mix plus some instant pudding and buttermilk to make it even more scrumptious!

PREP. Preheat oven to 350°F.

DRY INGREDIENTS. Add lemon cake mix and pudding mix to a medium bowl.

WET INGREDIENTS. Add buttermilk plus the ingredients on the back of the cake mix box to the cake mix and pudding mixture and beat until well combined.

BAKE. Pour the cake batter into a greased 9×13 pan. Bake for 23-35 minutes (or for more slices and thinner cake, use an 11×15 pan and bake for 18-20 minutes).

COOL + FROST. While the cake is cooling, make the cream cheese frosting by creaming together butter and cream cheese.

Add powdered sugar, vanilla, Jell-o mix (gelatin), lemon juice, lemon zest, and milk. Whisk until smooth.

Frost the cake and ENJOY!

Lemon sheet cake mix poured in bowl.

Recipe Tips

Lemon zest. Making lemon zest is very simple. Wash the lemon. Zest before juicing.

Using a grater or a traditional zester, simply rub the lemon against the blades of the grater or zester, making sure to only grate the outermost peel of the lemon. Zesting adds great citrus flavor!

Cake mix. I used a 15.25 box of lemon cake mix. The ingredients on the back included 1 cup water, ½ cup vegetable oil, and 3 large eggs. Purchase a cake mix that is similar in size and purchase the ingredients that are listed on the back of the box.

Pudding. Substitute the white chocolate pudding mix with a vanilla-flavored instant pudding mix. Sugar-free pudding also works just fine! Be sure that it is the instant kind and only use the pudding powder in the recipe, DO NOT make the pudding.

Toppings. 

Lemon sheet cake batter mixed in glass bowl.

Sheet cake tIPS

A traditional sheet cake is a rectangular single-layered cake. It can vary in length and width, but it is usually about 2 inches in height. Easily make a double-layered sheet cake. 

The ingredients of a sheet cake are often the exact same as round cakes or layered cakes.

Different-sized pans. A half sheet cake is 9×13 inches, a medium sheet cake is 11×15 inches, and a large sheet cake is 12×18 inches.

One trick to make a larger sheet cake is to bake 2-3 smaller cakes, place them side by side on a serving tray, and frost them as if it is one large cake. 

  • Large sheet cake. Make the cake a little thinner and use an 11×15 pan to get more slices out of it. The estimated cook time is 17-20 minutes.
  • For smaller-sized pans and circle pans, adjust the cook time to about 35-40 minutes, or until a toothpick poked into the center comes out clean. The cake may have a rounder top. As it cools it will flatten as seen in the recipe video.

Sheet cake servings are usually cut party size 1½x2 inch, or wedding size 1×2 inch.

Spreading frosting onto cooled lemon sheet cake.

Storing Info

Make ahead of time. Assemble the cake completely and cover the top with a lid or plastic wrap and leave it in the fridge. Take it out of the fridge 2 hours before it’s served to let it come to room temperature.

  • To avoid the cake from drying out, store it (without frosting) covered with plastic wrap, at room temperature.
  • Make the Lemon Cake Icing right before serving. If made beforehand, store the frosting in the fridge in an airtight container. Take it out 2 hours before frosting the cake so it can come to room temperature and go on smoothly.

STORE leftovers covered with plastic wrap in the fridge for 5-6 days. Take it out of the fridge an hour before serving to give the frosting time to get to room temperature.

Do not store this cake at room temperature for longer than 8 hours because of the cream cheese in the frosting.

FREEZE the Lemon Sheet Cake before or after frosting it.

  • To freeze unfrosted. Wrap the cooled cake with plastic wrap and again with foil. Freeze for up to 3 months. Unwrap before thawing. The frosting can be frozen in a separate container for 3-4 months. Thaw before using.
  • Freeze the frosted cake whole, or in slices. Place the cake in the freezer until the frosting has hardened, then wrap it with plastic and foil. The cake is best when eaten within 3- 4 months, but can last for 5-6 months. 
Homemade lemon sheet cake with lemon frosting on a white plate.

Recipe FAQ

What size box of cake mix should I use?

I used a 15.25 box of lemon cake mix, specifically Duncan Hines. Purchase a box of cake mix that is similar in size and make sure you also have the ingredients that are listed on the back.

What should I use if I can’t find white chocolate pudding?

If you can’t find white chocolate flavored pudding, I would use vanilla or lemon flavored. Make sure it’s the instant pudding!

Why did my cake fall? Why is it dense/soupy?

One of the main culprits is buying a cake mix that already has pudding in it. Make sure your box of cake mix does NOT already have pudding. Or, if it does, omit the instant pudding mix when making the cake batter.

And for more lemon treats:

4.87 from 59 votes

Lemon Sheet Cake Recipe

By: Lil’ Luna
Bright Lemon Sheet Cake with creamy lemon buttercream frosting is a sunny dessert perfect for feeding a crowd!
Servings: 24
Prep: 10 minutes
Cook: 25 minutes
Total: 35 minutes

Ingredients 

Cake

  • 1 box lemon cake mix plus ingredients on box
  • 1 cup buttermilk
  • 3 oz white chocolate instant pudding mix

Frosting

  • 1/4 cup butter softened
  • 4 oz cream cheese softened
  • 2 cups powdered sugar
  • 2 tbsp lemon jello mix
  • 1 tsp vanilla extract
  • 1 tbsp lemon juice you can use more if you want more lemon taste
  • 2-3 tsp lemon zest
  • 1-2 tbsp milk

Instructions 

  • Preheat oven to 350°F.
  • Add lemon cake mix and pudding mix to a medium bowl.
  • Add buttermilk plus the ingredients on the back of the cake mix box and beat until well combined.
  • Pour into a greased 9×13 pan. Bake for 23-35 minutes (or for more slices and thinner cake, use an 11×15 pan and bake for 18-20 minutes.
  • While the cake is cooling, make the frosting by creaming together butter and cream cheese. Add powdered sugar, vanilla, jello mix, lemon juice, lemon zest, and milk. Beat until smooth.
  • Frost cake and ENJOY!

Video

Nutrition

Calories: 174kcal, Carbohydrates: 32g, Protein: 1g, Fat: 4g, Saturated Fat: 2g, Cholesterol: 11mg, Sodium: 225mg, Potassium: 30mg, Sugar: 23g, Vitamin A: 140IU, Vitamin C: 0.5mg, Calcium: 63mg, Iron: 0.5mg

Nutrition information is automatically calculated, so should only be used as an approximation.

Additional Info

Course: Dessert
Cuisine: American
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About Kristyn

My name is Kristyn and I’m the mom of SIX stinkin’ cute kids and the wife to my smokin’ hot hubby, Lo. My mom’s maiden name is Luna, and I’m one of the many crafty “Lil’ Lunas” in the fam. On this site I like to share all things creative - from recipes to home decor to gifts and home decor ideas. Welcome!

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Recipe Rating




111 Comments

  1. 5 stars
    I do some catering for a woman’s golf league.
    They absolutely love this cake!! I followed the directions as written and it always turns out delicious!
    Great recipe!

  2. 5 stars
    I made this as the recipe stated, using the Duncan Hines cake mix. It turned out wonderfully! Nice, a bit denser texture and a great frosting! Lovely lemon flavor. I didn’t need to add the milk. The recipe wasn’t clear whether to remove it from the pan so I did not. Turned out perfectly bec there wasn’t enough frosting to do the sides as well. I will definitely make again – but increase the amount of frosting (I love frosting!!!). Made a perfect lemon cake for my mom’s birthday! She loved it! Thanks!