Pistachio Pudding Cake (Watergate Cake)
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Pistachio pudding cake, also known as Watergate Cake is full of rich and nutty pistachio flavors and makes an easy moist but thicker cake. This classic cake is topped with a fluffy frosting and plenty of crunchy chopped pistachios, and makes a pretty green cake that’s easy enough for any beginning baker to make.
Table of Contents
Why We Love Pistachio Pudding Cake
- Rich Pistachio Flavor – Pistachio pudding allows us to have a richer pistachio flavor in this cake without tons of effort. Pistachios have a distinct flavor which is nutty, sweet and earthy, but the flavor of the nut tends to be more subtle. The pistachio instant pudding not only adds that flavor, it also makes a rich and moist cake just like it does in my pistachio pudding cookies. Pistachio lovers will love this easy pistachio cake recipe.
- Classic Vintage Recipe – This is a vintage recipe that my mother in law would make for a special occasion, and my husband has fond memories of enjoying around the family table. It’s similar in flavor to Watergate salad which is more of a delicious dessert than a salad, and appeared on tables across the US about the same time.
- Fun For The Whole Family – This cake is an easy cake with simple ingredients that doesn’t require a lot of decorating skills, and the whole family can enjoy together. Plus both the cake and the frosting have a lovely green hue color.
This easy dessert feels super festive for Christmas, but also the perfect cake for St. Patrick’s Day, Easter, backyard bbqs and other spring or summer parties or family gatherings.
We are lucky a family member still had the recipe when my husband was craving this cake.
Ingredients For Pistachio Pudding Cake
For the Cake
- 15.25 ounces yellow cake mix 1 box, you can use white cake mix also.
- 5.1 ounces instant pistachio pudding can use a pack and a half of the smaller packs. Please note you will need boxed pudding mixes for both the cake and the frosting.
- 3 large eggs
- 1 cup club soda can also use a lemon-lime soda
- 1 cup butter melted, salted is fine for this recipe
- 1 cup pistachios shelled and chopped, plus extra for garnish on frosting below, measure after removing shells. I prefer unsalted but salted can work as long as they are lightly salted.
For The Frosting
- 5.1 ounces instant pistachio pudding
- 1 ¼ cup milk
- 8 ounces whipped topping like Cool Whip, I recommend using the full fat whipped topping for this cake
- Pistachios chopped, optional garnish
- Maraschino cherries optional garnish
Cake Mix Note
This recipe was developed with a 15.25 ounce cake mix. Some of the cake mix brands have been decreasing the size to 13.25 ounces. If you use only 13.25 ounces of cake mix the recipe may not be as successful so check the box carefully.
You could also add 1/4 cup from a second box of mix to make up the extra missing 2 ounces from the smaller-sized box. Some readers have reported they have added 1/4 cup of flour extra to make up the difference. I have not tested this in every recipe here, so it may not be successful for every recipe on this site.
How To Make Pistachio Pudding Cake
Making The Cake
- Preheat the oven to 350 degrees. Line a square 9 x 13 glass pan with parchment paper or grease well with cooking oil or a baking nonstick spray. Place the butter in a small bowl. Melt the butter in the microwave, about 1 minute.
- In a large bowl add the yellow cake mix, the first box of instant pistachio pudding mix, eggs, club soda and melted butter. Stir until fully mixed with a spatula or an electric mixer.
- Chop the pistachios coarsely. Fold in the pistachios into the batter.
- Pour batter for the cake into the prepared pan. Bake in the oven for 35- 40 minutes or until cooked all the way through. Let the cake cool in the pan completely, at least 45 minutes. As a general rule, the cake should be cool to the touch.
Making The Frosting
- In a second large bowl add the second instant pudding mix and the milk. With a metal whisk, blend together the pudding mix and the milk.
- Add the whipped topping into the pudding mix. Fold the whipped topping into the mixture with a silicone spatula.
Taste the frosting before frosting the cake. If you prefer a little more pistachio flavor in the frosting, try blending in 1/2 teaspoon of vanilla extract and 1/4 teaspoon of almond extract. Almond extract in particular helps bring out the nutty flavor of pistachio, and the combination is extra delicious.
- Frost the cooled cake. Top with chopped pistachios and optional maraschino cherries, then slice and serve.
Variation Ideas
Maraschino cherries can be added to each individual slice of cake, and they make a really pretty garnish on top. My mother in law never served the cake with cherries which is why I have made them optional, but I do think they look really pretty on a slice of this cake, especially for Christmas.
Some people add coconut to this recipe. Coconut can be added to the cake batter itself when you add the pistachios (I’d start with 1/2 cup of shredded coconut.) Coconut can also be sprinkled on top of the frosting.
Watergate Salad has crushed pineapple in the sweet dessert salad itself. Some people do like to add pineapple to the cake itself. If you want to add pineapple, I recommend using about a cup of crushed pineapple or well-chopped pineapple. Drain any excess liquid away from the pineapple well before folding it into the cake batter.
Some families add mini marshmallows to the top of the frosting, and you can too if you prefer!
Where Did This Classic Pistachio Pudding Cake First Come from?
This pistachio pudding cake first appeared during the Nixon era with pistachio pudding coming out on the market about two years after Nixon left office.
While there is a lot of speculation about how both classic Watergate salad and Watergate cake got its name, my favorite explanation is simply that the cake is “just full of nuts” like the politics felt like of that time. You can learn more about the history of Watergate cake and Watergate salad here.
That’s about as much politics as I want to talk about here, back to baking!
Can I Make This Cake Ahead Of Time?
You can make this cake up to 24 hours in advance for it to taste it’s freshest.
How Long Will Pistachio Pudding Cake Last?
Expect this cake will last about 4-5 days. Store the cake in the refrigerator in a covered airtight container or tightly with plastic wrap for best results.
Pistachio Pudding Cake (Watergate Cake)
Ingredients
For the Cake
- 15.25 ounces yellow cake mix 1 box
- 5.1 ounces instant pistachio pudding can use a pack and a half of the smaller packs
- 3 large eggs
- 1 cup club soda can also use a lemon-lime soda
- 1 cup butter melted,salted
- 1 cup pistachios shelled and chopped, plus extra for garnish on frosting below
For The Frosting
- 5.1 ounces instant pistachio pudding
- 1 ¼ cup milk
- 8 ounces whipped topping like Cool Whip
- Pistachios chopped, optional garnish
- Maraschino cherries optional garnish
Instructions
Making The Cake
- Preheat the oven to 350 degrees. Line a square 9 x 13 glass pan with parchment paper or grease well with cooking oil or a baking nonstick spray. Place the butter in a small bowl. Melt the butter in the microwave, about 1 minute.
- In a second large bowl add the yellow cake mix, the first box of instant pistachio pudding mix, eggs, club soda and melted butter. Stir until fully mixed with a spatula or an electric mixer.
- Chop the pistachios coarsely. Fold in the pistachios into the batter.
- Pour batter for the cake into the prepared pan. Bake in the oven for 35- 40 minutes or until cooked all the way through. Let the cake cool in the pan completely, at least 45 minutes. As a general rule, the cake should be cool to the touch.
Making The Frosting
- In a second large bowl add the second instant pudding mix and the milk. With a metal whisk, blend together the pudding mix and the milk.
- Add the whipped topping into the pudding mix. Fold the whipped topping into the mixture with a silicone spatula.
- Frost the cooled cake. Add chopped pistachios and optional maraschino cherries to the top of the cake, then slice and serve.
Notes
Nutrition
Did You Make This?
I would love to see it! Share your thoughts with me in the comments below!