Hello,

I am going to be making a sweet 16 cake and it is going to be filled with fresh raspberry buttercream and a layer of fresh raspberries. It will all be frosted with the fresh raspeberry buttercream as well. My questions is whether the raspberries in the buttercream will affect the fondant??? And how long will it keep? Can I make it on a Thursday for a party on Saturday afternoon??

This is the recipe I will be using:

3/4 cup unsalted butter, at room temperature
2 cups powdered sugar
1 cup fresh raspberries
1/2 teaspoon pure vanilla extract

In a food processor or blender, puree the raspberries. Pour raspberries through a fine sieve into a bowl, pressing on solids, to eliminate the seeds. Place butter, half of the powdered sugar, and raspberry puree into mixing bowl. Beat over low speed until well-blended. Add the other half of the sugar, increase speed to medium. Mix until light and fluffy.

THANK YOU!

has to be kept fridged--i would not use this formula if it was me but i don't have any direct knowledge of how it will do with fondant--if it's kept cold it should be fine is my best guess--

i'm sure others will chime in--

but i would want to take that raspberry juju and cook it down to intensify the raspberry flavor--

but i would test that recipe first and all that too--

AMy guess is that that recipe is barely going to hold up on its own, let alone under fondant.

so would you suggest I cook the raspberries and then add to creamed butter and powdered sugar? would that hold up better?

AI see no reason why the frosting wouldn't hold up, but I'm pretty inexperienced with American butter cream and the ratios.

Those fresh raspberries are going to squish and leech juices though. I would cook them down, like k8 suggested, not just for the frosting but also the filling. the only time I'll use fresh berries between layers is for Victoria sandwich cakes and shortcake type things. As they break down inside the cake, your layers will continue to settle as well. You don't end up with the nice plump fresh berries you started with, instead pulpy soggy cake.

personally, I'd do a meringue buttercream, and mix in as much cooked down raspberry puree as you can get into it. It tastes really fresh, and the sweetness doesn't compete with the berries luke an ABC would.

The last time I used fresh raspberries I cooked them down with reg. sugar, cornstarch and a little lemon juice.  After putting it through a sieve, I still had to remove some of the juice (save for flavoring).  When I used it for a filling, I put a thin layer of (in my case) SMBC on the cake so it would not completely sink into the cake with a ribbon of raspberry SMBC on top of the raspberries.  I still got a little shrinkage.

My frosting didn't have the raspberry mixture with the seeds because I was concerned about being able to get my fondant smooth without little bumps  - so I never tried it. Hope that made sense. :)

I forgot to add I used a little water to help the sugar dissolve.

The recipe looks yummy for a filling, maybe, but very, very soft for an icing [especially under the weight of fondant]. 

When I do a raspberry buttercream, I mix in high quality seedless raspberry preserves--usually Dickinson's .  I think the pectin and corn syrup in them keeps the icing stiffer.  I find the result very workable and quite delicious.  It holds up nicely under fondant, too.