clock clock icon cutlery cutlery icon flag flag icon folder folder icon instagram instagram icon pinterest pinterest icon facebook facebook icon print print icon squares squares icon
overhead image of Key Lime Pie Layer Cake

Key Lime Pie Layer Cake

  • Author: Lindsay
  • Prep Time: 50 minutes
  • Cook Time: 28 minutes
  • Total Time: 1 hour 18 minutes
  • Yield: 12-14 Slices
  • Category: Dessert
  • Method: Oven
  • Cuisine: American


This Key Lime Pie Layer Cake is a delicious cake version of key lime pie! It’s made with layers of key lime cake, key lime frosting with a touch of sweetened condensed milk and graham cracker crumbs!



  • 3/4 cup (168g) unsalted butter, room temperature
  • 1 1/2 cups (310g) sugar
  • 3/4 cup (174g) sour cream, room temperature
  • 1 tsp vanilla extract
  • 1 tbsp key lime zest (34 key limes)
  • 6 large egg whites, room temperature, lightly beaten
  • 2 1/2 cups (325g) all purpose flour
  • 4 tsp baking powder
  • 1/2 tsp salt
  • 1/2 cup (120ml) milk, room temperature
  • 2 tbsp (30ml) water, room temperature
  • 6 tbsp (90ml) key lime juice


  • 1 cup (134g) graham cracker crumbs
  • 1 tbsp sugar
  • 3 tbsp (42g) butter, melted


  • 3/4 cup (168g) salted butter
  • 3/4 cup (144g) shortening
  • 6 cups (690g) powdered sugar
  • 2 1/2 tbsp (38g) key lime juice
  • 1/4 cup (60ml) sweetened condensed milk
  • Yellow and leaf green icing colors


  • 1/4 cup (60ml) sweetened condensed milk
  • 1/2 cup (58g) powdered sugar
  • 2 tbsp (30ml) key lime juice
  • 2 lime slices, quartered


1. Preheat the oven to 350°F (176°C). Line the bottom of three 8-inch cake pans with parchment paper and grease the sides.
2. In a large mixing bowl, beat the butter and sugar together on medium speed until light in color and fluffy, 3-3. minutes.
4. Add the sour cream, vanilla extract and key lime zest and mix until combined.
5. Add the egg whites in two batches, mixing until incorporated after each addition. Scrape down the sides of the bowl as needed to make sure everything is combined.
6. Combine flour, baking powder and salt in a medium bowl. Combine the milk, water and key lime juice in a small measuring cup.
7. Add half of the flour mixture to the batter and mix until combined. Add the milk mixture to the batter and mix until combined. Add the remaining flour mixture and mix until smooth. Scrape down the sides of the bowl as needed to ensure everything is being combined.
8. Divide the batter evenly between the prepared cake pans. Bake for 22-24 minutes, or until a toothpick inserted in the middle comes out with a few crumbs.
9. Remove cakes from the oven and allow to cool for 3-4 minutes, then remove from pans to a cooling rack to finish cooling.
10. In a small bowl, combine the graham cracker crumbs, sugar and melted butter until crumbly, then spread onto a lined cookie sheet. Bake at 350°F (176°C) for 5 minutes, then remove and set aside to cool.
11. To make the frosting, beat butter and shortening together until smooth.
12. Add about half of the powdered sugar and mix until smooth.
13. Add keep lime juice and sweetened condensed milk and mix until smooth.
14. Add remaining powdered sugar and mix until smooth. Color the frosting with the yellow and leaf green icing colors. I used a very small amount of both. It won’t take much to get a nice lime green color.
15. When you are ready to build the cake, remove the domes from the cakes with a large serrated knife, so that they are flat.
17. Add the first layer of cake to a serving plate or a cardboard cake circle.
18. Top the cake with a layer of frosting. To get the frilly edges like I have, I used the Ateco 844 icing tip.
19. Top the frosting with about 1/3 of the graham cracker crumbs.
20. Add the second layer of cake and repeat steps 18 and 19 with the second layer of cake, then top the cake with the third layer of cake.
21. Spread about half of the remaining frosting onto the top of the cake, then pipe frosting around the edges. I used Ateco tip 808, a large round tip.
22. Sprinkle more graham cracker crumbs over the top of the cake and around the base of the cake, if desired.
23. Combine the additional sweetened condensed milk, powdered sugar and key lime juice in a small bowl, then use a spoon to place the drizzle around the outside edges of the cake. Finish off the cake with the key lime slices.


If you can’t find key limes or they aren’t in season, you can use the bottled key lime juice. In that case, for the zest and key limes for decoration, just use regular limes.

Keywords: key lime cake recipe, key lime cake, key lime pie recipe, easy key lime pie recipe, best key lime pie recipe, how to make key lime pie, key lime cake, key lime recipe, lime cake