White Chocolate Vanilla Marshmallow Cake Bars


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I love white chocolate.

White Chocolate Vanilla Marshmallow Cake Bars

And I have a thing for layered bars

White Chocolate Vanilla Marshmallow Cake Bars

Some people say white chocolate is too sweet.

White Chocolate Vanilla Marshmallow Cake Bars

Are you kidding me?

Nothing is too sweet for me.


White Chocolate Vanilla Marshmallow Cake Bars

Those same people who complain about desserts being “too sweet” will probably say these bars are “too rich” for them.


Nothing is too rich for me.

White Chocolate Vanilla Marshmallow Cake Bars

I just don’t think desserts can be too sweet or too rich.



White Chocolate Vanilla Marshmallow Cake Bars

Or too gooey.

White Chocolate Vanilla Marshmallow Cake Bars
If you disagree, then just go back for a second helping of broccoli.  I’ll take a second helping of these.


White Chocolate Vanilla Marshmallow Cake Bars (4 Layers)


Cake Layer (1st/base layer)

1/2 c butter, softened

1 box vanilla, white, or yellow cake mix (I used yellow)

1 egg

1 tsp vanilla extract


Marshmallow/Peanut Butter Layer (2nd layer)

2/3 c marshmallow creme

2/3 c peanut butter

1 can (14 oz) sweetened condensed milk

1 tsp vanilla extract


White Chocolate Layer (3rd layer)

1 bag (12 oz) white chocolate chips


White Chocolate Vanilla Buttercream Frosting Layer (4th/ top layer)

1/4 c butter (half stick)

1/3 c white chocolate (I used 2 baker’s squares of white chocolate, or use white chocolate chips)

2 c powdered sugar (variable from 1.5 to 3 cups based on desired consistency)

2 tbsp cream (or milk.  I used Coffeemate Vanilla coffee creamer)

1.5 tsp vanilla extract



1. Preheat oven to 350F and line a 9×13 pan with foil and spray well with cooking spray.

2. For the cake (1st/base) layer: Place stick of butter into a large bowl and microwave until the butter is softened (or just plan ahead and soften it at room temperature over time).  Add cake mix, egg, and vanilla extract to the softened butter and mix with a spoon or your hands until well combined.  It will be the consistency of very thick cookie dough and if it’s just not quite all combining, add 1 or 2 tbsp of water as needed.  Press dough into prepared baking pan.

3. For the marshmallow/peanut butter (2nd) layer: Place marshmallow creme, peanut butter, condensed milk, and vanilla extract into a large bowl and mix until well combined.  Pour over the dough.

4. For the white chocolate (3rd) layer: Sprinkle the white chocolate chips evenly over the top of the marshmallow/PB layer

5. Bake for 20-23 minutes at 350F.  Center may seem somewhat jiggly, but will set up while cools.  Don’t overbake.  You want these gooey.

6. While bars are baking, make the white chocolate vanilla buttercream frosting (4th/top) layer: Add butter and white chocolate to a microwave-safe bowl and melt in the microwave in 30-45 second increments, removing from the heat, and stirring and re-microwaving until melted and smooth.  Don’t scorch the white chocolate.  Add powdered sugar, cream, and vanilla extract and stir until smooth and is in a semi-pourable consistency.   For thicker frosting, use less cream or more powdered sugar.  Play around with ratios to your liking.

7. After the bars are out of the oven, allow to cool for about 5-10 minutes and then drizzle the frosting over the top.   You can also frost them in entirety rather than drizzling (you will likely have enough frosting to do so).

8. Allow to cool well before slicing and serving.  Expedite this by placing in the fridge or freezer.

Notes: To make this gluten free, use GF cake mix.

To make this vegan, in place of the egg, use a chia or flax egg like I instructed how to do in this recipe.  Use margarine in place of butter.  Use full fat coconut milk sweetened with agave for the sweetened condensed milk.  Use vegan white chocolate and vegan marshmallows<– Lots of tweaks, yes, but not impossible.



A Visual Guide:

Gather your ingredients for the cake/base layer

Ingredients for White Chocolate Vanilla Marshmallow Cake Bars

Make the dough

Dough of White Chocolate Vanilla Marshmallow Cake Bars

Press dough into pan

Dough of White Chocolate Vanilla Marshmallow Cake Bars

Gather the ingredients for the marshmallow/peanut butter layer

Ingredients on countertop

Make mixture and spread over the top of the cake layer

cake layer

Add the white chocolate chips

white chocolate chipsDoesn’t that look good!

Chip nirvana. That’s what I imagine the pearly gates of heaven looking like.

Place pan in oven to bake and while your pan ‘o heaven is baking make the white chocolate vanilla buttercream frosting.

Don’t just straight up drink this.  But I wanted to.

After bakingWhite Chocolate Vanilla Marshmallow Cake Bars


Afternd cooling 5-10 minutes, drizzle the white chocolate vanilla buttercream frosting over the top  and (or frost bars in entirety rather than drizzling since the frosting recipe will make a bit extra)

White Chocolate Vanilla Marshmallow Cake BarsWhite chocolate ribbons and swirls. 

Just taking these pictures was euphoric for me.

White Chocolate Vanilla Marshmallow Cake Bars

Cool, slice, and serve

White Chocolate Vanilla Marshmallow Cake Bars

These are crazy good.

The cakey layer, then the gooey peanut butter vanilla sweetened condensed milk and marshmallow layer that just melts in your mouth

And the crunch of the white chocolate chips

All topped with white chocolate vanilla buttercream frosting. 

Oh these are totally fat free and calorie free, did I mention?

They are probably the best bars I’ve made in recent memory. 

Or ever.

White Chocolate Vanilla Marshmallow Cake Bars

There’s a wonderful cakey-ness to them because of the cake layer at the bottom.  A bit white chocolate blondie-like.

White Chocolate Vanilla Marshmallow Cake Bars

But because of everything else going on in the middle layer: the marshmallow creme, the peanut butter, all that vanilla…

White Chocolate Vanilla Marshmallow Cake Bars…even after they’re baked, they’re still semi-drippy in the middle layer.

Sort of oozing.

That would be a marshmallow-cremey-peanut-buttery-vanillaey oozey, luscious, drippy mess.

With white chocolate chips everywhere.

And white chocolate buttercream frosting on top

Overhead of two bars on white plate

It sort of crackles as it cools.  Mmmm, good.

Overhead of one bar on plate

It’s one good thing after the next as you sink your teeth into one of these sugar bombs.

Two stacked White Chocolate Vanilla Marshmallow Cake Bars on plate
And yes, they are sweet.  And rich. 

But I already covered that.

Overhead of two stacked White Chocolate Vanilla Marshmallow Cake Bars on plateIf you don’t like sweet desserts, or rich desserts, then skip these. 

Go eat beans or celery sticks or cardboard or something less sweet and less rich.

But if you’d like to be transported to heaven (or at the very least transported to the dentist from the cavities you may get from these) then go ahead and make these.

Four White Chocolate Vanilla Marshmallow Cake Bars on white plate stacked

You will thank me later for the peer pressure.

Close up of bars stacked on plate showing layers

Close up of two stacked bars on plate


1. What’s your favorite dessert bar

Not talking cookies or pies or cakes. 

I’m talking bars, blondies, or brownies

In recent memory the highest praises goes to

Fudgy Nutella Brownies with Cream Cheese Frosting

Magic Eight Bars

Nutter Butter Special K Bars (No Bake)

Special K Bars (No Bake)

Honorable Mention: Chocolate Chip Cookie Dough & Marshmallow Stuffed Rice Krispie Bars

I happen to love bars.  Maybe it’s my Minnesota upbringing where bringing a pan of bars was standard protocol for everything from graduation parties to funeral luncheons to bridal showers.  You just brought bars.

2. Do you like White Chocolate?

I love it!

I am adding this recipe to my White Chocolate Recipes Collection post

Need other white chocolate ideas?

No Bake White Chocolate & Mango Cookie Dough Bites

PB Cups with Half White Chocolate/Half Dark Chocolate Outside with Chocolate PB Center

White Chocolate Blondies with Chocolate Peanut Butter Frosting

All around I have nothing but love for white chocolate.

3. What’s the best thing you ate or did over the weekend?

I had a big and busy week!

These bars ranked right up there a best thing as did the other dessert I made and mentioned in my last post, Ooh La La

If you’re just catching up on posts from the weekend, here are mine since Friday:

Have a great start to your week!


Leave a Comment

Please note: I have only made the recipe as written, and cannot give advice or predict what will happen if you change something. If you have a question regarding changing, altering, or making substitutions to the recipe, please check out the FAQ page for more info.


  1. The bars seem very “wet” to me compared to almost all other bars I’ve ever seen. Were the pictures taken before the bars had a chance to set? They look as though when someone goes to eat a bar everything is going to just run everywhere. I guess I’m puzzled what’s happening with these.

  2. I usually make a fluffernutter version of these…. and use butter flavored box cake….. and add semi sweet chocolate chunks on top of the white chocolate chips…chocolate on chocolate on peanut butter on butter goodness.
    just sayin. :)

  3. Recipe looks so good! I’m not sure if you’ve ever tried to bake these with the gluten free cake mix, but I just did and they didn’t turn out well at all. The cake bottom did not bake well at all. I let them cool them stuck them in the fridge overnight and the instantly fell apart. I’d like to try again, but would you suggest I bake the cake bottom a little bit before layering or just leave the whole thing in their a little longer? I usually do very well with following & baking, but I should have taken into account the difference with the GF cake. Don’t worry I can still eat it with a spoon!

    1. GF baking and regular baking are totally different and unfortunately this is a case where just swapping in GF for regular mix doesn’t work so well. Since I’ve never tried this exact recipe with a GF mix I really don’t even have a way to troubleshoot. But glad that spoon works well for you :)