White Chocolate Vanilla Marshmallow Cake Bars

I love white chocolate.

And I have a thing for layered bars

Some people say white chocolate is too sweet.

Are you kidding me?

Nothing is too sweet for me.


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.

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


Or too gooey.

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

Make the dough

Press dough into pan

Gather the ingredients for the marshmallow/peanut butter layer

Make mixture and spread over the top of the cake layer

Add the white chocolate chips

Doesn’t that look good!

Chip nirvanaThat’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 baking

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 ribbons and swirls. 

Just taking these pictures was euphoric for me.

Cool, slice, and serve

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.

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

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

…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

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

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

And yes, they are sweet.  And rich. 

But I already covered that.

If 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.

You will thank me later for the peer pressure.


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!



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