Duncan Hines Key Lime Cake Recipe: Zesty Citrus Layers With Creamy Frosting

This layered cake transforms boxed mix into a creamy, citrus-infused masterpiece with minimal effort. The secret lies in enhancing the batter with fresh key lime zest and juice.

Each moist layer bursts with tangy flavor, perfectly balanced by a smooth frosting that’s rich yet light. The result is a dessert that tastes homemade, not boxed.

Ingredients for Duncan Hines Key Lime Cake

Boxed mix elevated with fresh citrus and creamy frosting for a bakery-worthy dessert.

The Duncan Hines Classic Yellow Cake Mix provides the perfect base—15.25 oz boxes are standard at most grocery stores. For the key lime juice and zest, seek out fresh key limes (smaller, more aromatic than regular limes) at Whole Foods or Latin markets. The cream cheese must be full-fat Philadelphia brand for optimal texture and stability in the frosting.

No key limes? Regular lime juice and zest work in a pinch (use one-third more for comparable tang). For a lighter frosting, substitute Greek yogurt at half the amount of cream cheese. The vegetable oil can be swapped for melted coconut oil (adds subtle richness). Skip the food coloring if you prefer a natural look—the lime zest already adds flecks of green.

Store unfrosted layers wrapped tightly at room temperature for 2 days. Frosted cake keeps in the refrigerator for 5 days or freezes beautifully for 3 months. Bring to room temperature before serving for the best texture and flavor.

Step-by-Step Instructions for Duncan Hines Key Lime Cake

Master the technique for moist layers and a velvety frosting that’s tangy yet perfectly balanced.

Step 1: Prepare the Key Lime Cake Batter

Preheat your oven to 350°F and grease two 9-inch round cake pans, then line the bottoms with parchment paper. This prevents sticking and ensures clean release after baking.

In a large mixing bowl, combine the 1 box Duncan Hines Classic Yellow Cake Mix, 0.5 cup Key Lime Juice, 2 tbsp Key Lime Zest, 3 whole Large Eggs, 0.33 cup Vegetable Oil, and 1.25 cups Water. Beat on medium speed for 2 minutes until the batter is smooth and fully combined.

The Key Lime Juice and Key Lime Zest infuse the batter with bright citrus flavor, while the oil keeps the crumb tender. The batter will be slightly thicker than traditional boxed cake mix due to the added zest.

Step 2: Bake the Cake Layers

Divide the batter evenly between the prepared pans, smoothing the tops with a spatula. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.

Watch for the edges to pull away from the pan and the tops to spring back when lightly pressed. Overbaking will dry out the layers, so start checking at 25 minutes. Remove the cakes from the oven and let them cool in the pans for 10 minutes before transferring to a wire rack to cool completely.

Step 3: Prepare the Cream Cheese Frosting

In a stand mixer fitted with the paddle attachment, beat the 8 oz Cream Cheese and 0.5 cup Unsalted Butter on medium speed for 2-3 minutes until smooth and creamy. Scrape down the sides of the bowl as needed to ensure even mixing.

Gradually add the 4 cups Powdered Sugar, 1 tsp Vanilla Extract, 0.25 cup Heavy Whipping Cream, and 2 drops Green Food Coloring, mixing on low speed until combined. Increase the speed to medium-high and beat for an additional 2-3 minutes until the frosting is light, fluffy, and pale green in color.

The Heavy Whipping Cream lightens the frosting, while the Green Food Coloring enhances the Key Lime aesthetic. Adjust the consistency with additional Powdered Sugar or Heavy Whipping Cream if needed.

Step 4: Assemble and Frost the Cake

Place one cooled cake layer on a serving plate or cake stand. Spread a generous layer of frosting over the top, then place the second layer on top. Use the remaining frosting to cover the top and sides of the cake, creating a smooth, even finish.

For a polished look, use an offset spatula to create swirls or peaks in the frosting. The frosting should be thick enough to hold its shape but still spreadable. Chill the cake for 30 minutes before slicing to allow the frosting to set slightly, making it easier to serve clean slices.

Storing and Reheating This duncan hines key lime cake

Room Temperature Storage

If serving within 2 days, store the unfrosted layers wrapped tightly in plastic wrap at room temperature. This preserves moisture without drying out the crumb. I keep mine in a cool, dark cupboard away from direct sunlight.

Refrigerator Storage

Once frosted, this cake keeps beautifully in the refrigerator for up to 5 days. I use an airtight cake carrier or cover it with plastic wrap to prevent the frosting from absorbing other flavors in the fridge. 💡

Freezer Storage

For longer storage, freeze unfrosted layers or the fully assembled cake. Wrap each layer individually in plastic wrap, then foil, and store for up to 3 months. The cream cheese frosting freezes well but may need a quick re-whip after thawing.

Thawing Properly

Move the cake from freezer to refrigerator 12 hours before serving. For faster thawing, place it on the counter for 2-3 hours at room temperature. Never microwave a frozen cake—it will become rubbery.

Reheating Slices

Individual slices taste best served at room temperature. If chilled, let them sit out for 30 minutes before serving. For a warm treat, microwave slices on 50% power for 10-15 seconds to soften the frosting. ❄️

Storage Tip

Always bring the cake to room temperature before serving for the best texture and flavor. The cream cheese frosting will soften slightly, making it easier to slice and more enjoyable to eat.

Frequently Asked Questions