Birthday Cake Disasters Narrowly Averted

Snolf the First’s birthday was the other day, and he requested a coconut cake. I didn’t have one in my repertoire, so I found a good prospect online. The only problem I saw is that it called for a lemon curd between the layers, and I knew Snolf I wouldn’t be too keen on that. Instead, I chose to make pastry cream, and flavor it with a bit of coconut-flavored rum. It wasn’t until I started making the frosting that I realized I had a fundamental compatibility problem.

Pastry cream is wonderfully flexible stuff—it can be flavored all kinds of ways and is useful as a cake filling, meringue topping, or as a thin, protective layer between a delectable tart pastry and fresh fruit. But it likes to be kept cold. I find that if it’s allowed to come to room temperature, it thins to unacceptable levels.

The cake could easily have been refrigerated to accommodate the pastry cream—but the frosting I chose could not. I wanted something light for the frosting, and chose 7-minute frosting. It’s been years since I’ve made it, but I recalled that with just a bit of care, it comes together very nicely. I forgot that it does not like cold—it gets soft and weepy, and the sugar starts to granulate out more quickly than usual.

I also forgot that 7-minute frosting requires beating while sitting atop a pan of simmering water. The problem there? Our kitchen is configured so that there is no electrical outlet close to the stove—and it has no electrical outlets on it, unlike some newer models. I thought I could get around that by heating the water, then removing it from the stove and beating the ingredients. That failed. I had granular gunk in the bowl after about ten minutes of beating.

I attempted it again, determined to give my son the cake he’d requested. This time I used the outlet closest to the stove, and interrupted the beating to reheat the water about halfway through the process. It worked—but just barely. The frosting was a little too soft, although it was beautifully glossy and smooth; and it did start to granulate sooner than is typical of these frostings.

As for the temperature issue, I opted to let the pastry cream seep into the layers, and keep the cake at room temperature until serving time. As that was just a few hours after the cake was assembled, it wasn’t a big issue. But I learned my lessons! 1. Make sure fillings and frostings are compatible; and 2. Make sure you can make 7-minute frosting before promising it.

Here’s the recipe I use for 7-minute frosting. It’s pretty much failproof, as long as the directions are followed carefully. (I’ve seen several online that look like they’re designed to fail.)

7-Minute Frosting

Covers one large sheet cake, one 10" tube cake, or a 9" layer cake (there’s enough to be used as the filling between layers)

1 1/2 C sugar
1/3 C cold water
2 egg whites (1/4 C)
1 T. corn syrup OR 1/4 t. cream of tartar
dash salt
1 t. vanilla

Bring a pan of water up to simmer on the stove; make sure the water level is low enough not to touch the mixing bowl when it’s placed on the pan.

In mixing bowl, combine all ingredients except vanilla. Beat about 30 s. on low speed, or just until combined. Place over boiling water; cook about 7 minutes while constantly beating at high speed. When done, the frosting will form stiff peaks. (It may take longer if the kitchen is humid.)

Remove from heat. Add vanilla and beat an additional 2–3 minutes, until the frosting is of spreading consistency.

Working fairly quickly, spread a thin layer over the cake to hold crumbs; then frost as desired, creating swirls or peaks with the frosting. Keep cake at room temperature until serving time. Frosting will start to become gritty as the sugar granulates after about 24 hours.

Variations: For peppermint frosting, replace vanilla with 1/4 t. peppermint extract, and garnish top of cake with crushed candy canes or other peppermint candy.
For seafoam frosting, substitute 1 1/4 C brown sugar for granulated sugar, and decrease cold water to 1/4 C.