Starts With A Cake Mix, Ends Up a Show-Stopper
Looking for an easy summer dessert that comes together quickly but looks like you spent hours? This rhubarb poke cake is exactly that. It’s simple to make, refreshingly cool, and impressive enough for guests. If your rhubarb patch is producing like mine—or a neighbor handed you a bundle—this recipe is a perfect way to use it.
Why You’ll Love This Rhubarb Poke Cake
- Quick and easy to prepare
- Cold, creamy, and ideal for warm weather
- Looks elegant without a lot of fuss
- A pleasing blend of simple prep and pretty presentation
- Make-ahead friendly—flavors deepen after chilling
If you enjoy rhubarb, try these reader favorites: One-Bowl Rhubarb Bread, Rhubarb Custard Pie, and Rhubarb Dump Cake.
How To Make This Pretty Rhubarb Poke Cake
1. Make the rhubarb topping
Start by combining finely diced rhubarb and sugar in a saucepan. Let it sit an hour or so to draw out juices—this softens the rhubarb and intensifies flavor.
Add water and simmer gently until the rhubarb is fully tender and breaking down. Stir in a small box of strawberry (or raspberry) gelatin and continue stirring until it dissolves. Set the mixture aside while the cake bakes. Reserve about 1/2 cup for decorating the top, if you like.
2. Bake the cake
Prepare a boxed yellow cake mix (white or lemon also work) according to package directions. Pour the batter into a greased 9×13-inch pan and bake at 350°F (175°C).
Bake until the top springs back when lightly touched, the edges pull slightly away from the pan, and a tester comes out clean. Avoid underbaking—the cake needs structure to hold the filling.
3. Poke and fill
While the cake is still hot, use the handle of a wooden spoon to poke holes all over the surface. Slowly spoon the warm rhubarb topping over the cake, using a rubber spatula to nudge it into the holes so the flavor sinks into the cake.
Chill the cake in the refrigerator until completely set, at least two hours.
4. Frost and decorate
For the lightest topping, thaw the whipped topping in the refrigerator for several hours or overnight. Avoid microwaving or leaving it at room temperature for long periods, which can cause it to lose volume.
Spread the whipped topping evenly over the chilled cake, pulling it to the edges. If you reserved rhubarb sauce for decoration, drizzle a few thin lines across the top. If that sauce has thickened, loosen it with a splash of warm water.
Use a table knife to drag through the lines in one direction and then the other to create a simple swirled pattern. That pretty finish is optional—served plain, the cake is still delicious.
Printable Recipe Card
Beautiful Rhubarb Poke Cake Recipe
This moist poke cake starts with a boxed yellow cake, is filled with a sweet-tart rhubarb sauce, and finished with whipped topping and a rhubarb swirl. A perfect, crowd-pleasing summer dessert.
15 minutes
25 minutes
3 hours
3 hours 40 minutes
Ingredients
Cake
- 1 boxed yellow cake mix (white or lemon also work)
- 3 eggs
- 1 cup water
- 1/2 cup vegetable oil
Rhubarb Sauce
- 1 small box strawberry or raspberry gelatin
- 2 cups finely diced rhubarb
- 1 cup sugar
- 1 1/2 cups water
Topping
- One small container whipped topping, thawed
- 1/2 cup reserved rhubarb sauce
Instructions
Prepare Rhubarb Sauce
- Pour 1 cup sugar over finely diced rhubarb and let sit for an hour to draw out juices.
- Add 1 1/2 cups water and simmer on low to medium until rhubarb is very tender.
- Stir in the gelatin and mix until fully dissolved. Reserve 1/2 cup for decorating and set the rest aside while the cake bakes.
Prepare Cake
- Prepare cake mix according to package directions. Bake at 350°F in a greased 9″ x 13″ pan for about 25 minutes or until a tester comes out clean.
- While the cake is still hot, poke holes across the surface with a wooden spoon handle. Pour the warm rhubarb sauce over the cake and coax it into the holes with a spatula.
- Refrigerate until the filling is set, at least two hours.
- Spread thawed whipped topping evenly over the chilled cake.
- Drizzle reserved rhubarb sauce in thin lines across the top. If needed, thin the sauce with a touch of warm water so it will drizzle.
- Drag a table knife through the lines in alternating directions to create a swirl pattern, or skip this step and serve plain.
Notes
This cake should be refrigerated. For the best texture and flavor, remove it from the fridge 10–15 minutes before serving. It’s a great make-ahead dessert for summer gatherings and holidays—decorate with fresh berries if you like.
Nutrition Information:
Yield:
15
Serving Size:
1
Amount Per Serving:
Calories: 277
Total Fat: 10g
Saturated Fat: 2g
Trans Fat: 0g
Unsaturated Fat: 7g
Cholesterol: 37mg
Sodium: 316mg
Carbohydrates: 45g
Fiber: 1g
Sugar: 30g
Protein: 3g
FAQs
Can I use a different flavor of cake mix?
Yes. White, yellow, or lemon cake mixes all work well. Lemon adds a bright note, while white or yellow lets the rhubarb flavor stand out.
What flavor of gelatin works best?
Strawberry is classic, but raspberry or cherry also pair nicely with tart rhubarb and give the topping a vivid color.
Can I make rhubarb poke cake ahead of time?
Yes. The cake is actually better after chilling for several hours, making it a great make-ahead choice for potlucks and summer gatherings.
Does this cake need to be refrigerated?
Yes. Because of the whipped topping and fruit filling, cover and refrigerate the cake until serving.
Can I freeze rhubarb poke cake?
You can freeze it, but whipped topping may soften after thawing. For best results, freeze before adding the topping, then thaw and decorate just before serving.
This dessert is a wonderful finish for a summer picnic or cookout. Serve it after classic sides like potato salad and coleslaw and enjoy those happy smiles.
If you try this recipe, feedback and reviews are always appreciated—thank you for reading and happy baking!
Love, GB (Betty Streff)