I made this Blueberry Swirl Cake today and I couldn’t be happier with the way that it turned out!
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I think everything about it looks delicious. I love the blueberry sauce running through the cake, and the color of the “frosting” is beautiful.
This is a perfect summer cake! It’s nice and light so it won’t weigh you down. Plus it is only 3 Freestyle points per serving.
The blueberry sauce for this cake is actually something I used before in my Blueberry FroYo Bark. I love it so much!
For the Blueberry FroYo Bark recipe, there is some of the sauce left over so I use it on toast, or with a waffle.
For this blueberry swirl cake I needed the sauce to be thinner, so after it cooked I put it in my Magic Bullet Blender. It comes in handy for recipes like this. Instead of getting out my blender or food processor I just use my Magic Bullet Blender.
The Magic Bullet is also great for helping with scrambled eggs or making smoothies. My kids use it all the time for smoothies. It’s that easy to use!
To get the blueberry sauce into the cake I used a condiment squeeze bottle. If you don’t have that you could also use a piping bag.
I also added some of the blueberry sauce to the top of the cake. Just be careful to not overdo it.
Once I was done I used a butter knife to swirl together the blueberry sauce and cake batter.
I did have some of the blueberry sauce left over, but I don’t think one cup of blueberries would have been enough.
While the cake was baking I made the frosting. It is 6 oz. of fat-free Cool Whip and 2 tablespoons of the blueberry sauce.
The blueberry sauce doesn’t give the Cool Whip a ton of flavor, but it makes it a beautiful color purple. I just love it!

Yield: 18 servings (3 points per serving for blue, green and purple)
- 2 cups blueberries
- 2 tablespoons sugar-free maple syrup
- 1 box Pillsbury sugar-free yellow cake mix
- 12 oz. diet 7UP
- 6 oz. fat-free Cool Whip
- Optional: 1 additional cup of blueberries for the top of the cake
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Preheat oven to 325 degrees F.
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Add the blueberries and sugar-free Maple syrup to a medium saucepan. Cook on low for 10 minutes.
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Run the blueberries through a Magic Bullet or blender. Reserve 2 tablespoons of the blueberry sauce.
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In a large mixing bowl stir together the sugar-free cake mix and diet 7Up. Whisk until smooth.
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Use a condiment squeeze bottle or piping bag to get the blueberry sauce into the cake. Add a few squirts to the top of the cake as well.
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Use a butter knife to add swirls to the cake.
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Place the cake in the oven and cook according to the directions on the box.
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While the cake is baking, add the cool whip and 2 tablespoons of the blueberry sauce together. Gently fold until the color is a solid light purple. Store in the fridge until ready to use.
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Once the cake has cooled add the Cool Whip frosting and serve.
If you’re looking for some zero point recipes, check out my post 20 Zero Point Recipes or my post 20 (More) Zero Point Recipes. Both are filled with delicious recipes that won’t cost you a single point! They’re perfect for days when you’re running low on points, or trying to save up points for a night out.
If you’re looking for dessert recipes you can visit 50 Weight Watchers Freestyle Desserts. It’s filled with delicious desserts perfect for Weight Watchers!

Can frozen blueberries be used if you thaw. Them and drain them?
I haven’t tried it but I don’t see why not.