As I mentioned previously, Swiss Meringue Buttercream (SMBC) is my absolute favorite frosting. It is so unbelievably good, once you try it you will NEVER want a different kind of frosting again. I first discovered SMBC when I was preparing for my wedding cake back in 2012 and I have never looked back. It may come off as a tricky frosting at first, but it is really not that bad to make and it is actually quite forgiving. So, as promised, here the is post on SMBC!
My dear brother and wonderful sister-in-law have been married for five years now, however, they never really got to properly celebrate with the extended family due to circumstances beyond their control. Long story short, my brother was in the Marine Corps stationed in California, was about to be deployed, and wanted to make it official with his sweetie before he went overseas. So my dad and I hopped on a plane and had the privilege and pleasure of being present at their wedding, which was really heart-felt and sweet. Unfortunately, all the other family members and friends in the Midwest did not get to come.
So, in honor their five year anniversary (and for an awesome excuse to have a party) they decided to have their wedding reception. Naturally, they asked me to do the cake and I was super pumped. The cake was a three-tier, fresh raspberry cake with fresh raspberry filling, and mint SMBC. I did a basket-weave pattern on all three tiers and added (fake) orchid blossoms. It turned out really pretty and quite delicious.
Now, without further ado, the SMBC! Below is the recipe I used for this cake. I ended up with about 3 cups of frosting left over.
Mint Swiss Meringue Buttercream Frosting
15 egg whites, LARGE ONLY, room temperature
3 3/4 cups granulated sugar
9 sticks of UNSALTED butter, room temperature, cut into cubes
*A note on the butter: Please DO NOT substitute salted butter in this recipe. The added salt will bring out the butter flavor WAY too much and no amount of flavoring will mask it! Trust me on this. The first time I made SMBC I only made a tiny batch to test out the technique. I didn’t want to run to the store for unsalted butter so I used the salted butter my mom had in her fridge. YUCK. The texture was great and I could see the potential for the frosting, but it tasted like whipped butter. Once again, DO NOT use salted butter!
a pinch of salt
2 teaspoons mint extract
Electric mixer with whipping attachment, beating attachment, and detachable mixing bowl.
Large sauce pan, which you will place your mixing bowl on top of; make sure it’s a snug fit.
As with any recipe, lay out all of your ingredients to make sure you have everything you need. You don’t want to be running to the store for more butter halfway through the recipe!
The first thing you want to do with Swiss Meringue Buttercream, and you absolutely MUST do this, is lay out your equipment and wipe EVERYTHING down with lemon juice. This eliminates any traces of grease that may be present which would ruin your meringue and thus destroy your SMBC. DO NOT FORGET TO WIPE EVERYTHING! The saucepan, the whisk… EVERYTHING!
Put about an inch of water in the sauce pan and get it simmering, but not boiling. You want it to make steam, but not bubble up and splash. Place your room temperature egg whites and sugar in the mixing bowl from your mixer and place on top of the sauce pan with simmering water. Using a wire whisk, whisk constantly until the sugar is completely dissolved and the egg whites are hot. To test if the sugar is fully dissolved, stick a clean finger in there and rub some of the mix between your thumb and forefinger – you should not feel any grains of sugar. If you feel grains, keep whisking; if it’s smooth as silk, you’re ready for the next step!
Bring your mixing bowl over to your mixer and while using the whisk attachment, begin to whip your egg whites and sugar mixture until the meringue is thick, glossy, and the bottom of your mixing bowl feels room temperature to the touch. FYI, this can take a while. Most recipes I’ve seen call for up to 10 minutes, but every time I’ve made SMBC, it takes me at least 20 – 30 before the meringue is stiff enough. Could be because of strength of my mixer, my crappy whisk attachment, or kitchen environment. I don’t know, but if it takes longer than 10 minutes, do not panic! Keep on whipping! You’ll know it’s the right thickness when you can make medium-stiffness peaks in the meringue. If you reach proper thickness and the bowl still feels warm, stopping mixing and let the bowl cool off. You do NOT want to add butter until the bowl is room temperature because it will melt!
Now that your bowl is room temperature and your meringue is gorgeous, you can begin to add butter. And yes, it is a lot of butter. This frosting is not for people on any sort of diet. Switch to your mixing beaters instead of the whisk and turn on the mixer to low. Add butter one cube at a time, incorporating between each addition. This is the scary part of making SMBC. Adding the butter ends up being not pretty for a while – your frosting will look like cottage cheese for a few minutes. You may find yourself thinking, “What have I done?!” Once again, DO NOT PANIC! Keep on mixing! It will come together, and it if doesn’t it could be a number of factors which I don’t have the time or expertise to diagnose, however, if you follow the recipe carefully, it should be fine! My overall advice is have hope and keep on mixing! Also, it doesn’t hurt to consult the All-Knowing Google Machine for trouble-shooting wisdom on the subject. Continue adding butter until you run out and continue mixing until the SMBC magically turns into velvety goodness. This can also take upwards of 10 minutes.
Once your SMBC baby has reached the velvety smooth texture you’re seeking, add the flavoring extract of your choosing and the pinch of salt. Continue to beat on low speed until well combined. It is at this point that you can add additional flavor extracts, fruit purees, or melted chocolate to achieve the perfect SMBC of your dreams.
If you’re not using it right away, store it in an air-tight container in the fridge. Just be sure to bring it to room temperature and re-whip it before you use it on your cake. As I mentioned in my post on American Buttercream, do not, I repeat, DO NOT microwave the frosting! I know it takes forever to come to room temperature if you just set it out on the counter, but you must be patient! You do not want to melt the frosting you worked so hard to make!
That being said, keep in mind that this frosting is essentially all butter, therefore, it does not hold up particularly well in hot or humid environs. If you’re doing a wedding cake, say, in the middle of July, like I did, keep the cake in an air-conditioned room or the fridge if it will fit until right before you serve the cake. That way, the frosting will retain its shape and yummy texture. Nobody likes melted frosting, so be sure to err on the side of caution!
What else can I say? Swiss Meringue Buttercream is AMAZING and everyone should try it at least once! But beware, once you have SMBC, you won’t want anything else!
If you have further questions or for trouble-shooting tips, check out these excellent blog posts on the subject: