Another June has come and gone, which means I’ve constructed another ludicrous birthday cake for Jack. This year we invited family and a handful of friends, plus their families, so the party checked a lot of his (and my) summer dream birthday boxes: kids running around the backyard giggling; adults happily ensconced in a variety of mismatched lawn chairs, beer in hand; an obscene number of water balloons; and a cake that would probably feed twice the number of guests we had (which already numbered near 30).

Given that we were bonkers enough to invite that many people to our house, I knew I needed to keep all of the food, including the cake, as simple and as make-ahead friendly as possible. I figured that Jack, like most kids his age, cared slightly less about the cake itself (which he refers to as “the bread” of the cake, ha) than whatever decorative monstrosities I could festoon it with. However, for the adults in our midst, the cake also needed to be delicious as hell. And - the kicker - I needed to be able to make the whole thing at least a day in advance.

The cake component: a yellow vanilla cake in layers. Truly a no-brainer, the blankest canvas for whatever I could dream up. Note that the actual birthday cake was not the demure cutie you see in photos here, but a hulking Valkyrie of a thing, a 3-layered sheet cake achieved with a number of sheet pans and miles of parchment.

The frosting was the real question. Buttercream can hang out in the fridge, but always feels fussy and I never am convinced I’ve gotten it right. If we ended up with a hot day, I knew I’d also erupt into nervous sweats for fear it would simply ooze off of the cake. Whipped cream is light, airy, and sure, kids love it, but it’s equally sensitive to weather, not particularly stable as a layering material, and doesn’t take kindly to being made too far in advance.

What resulted was a sort of whipped cream on steroids, stabilized by the addition of thick, barely-sweet mascarpone cheese, powdered sugar (not regular granulated), and cream of tartar, the secret backbone to meringues and other light-as-a-feather, stiff-as-you-need-them confections. Because Jack was born in strawberry season and continues to adore them, I swirled in a small pot of strained strawberry jam and a toothpick-tip’s worth of red gel pastry coloring. And lo, as I tasted my way through the process it occurred to me this was the only creamy topping I’d ever need or want again, birthday cake or anything else.

You could color and flavor yours with that same strawberry vibe or almost any other fruit jam or compote, or even caramel or ganache whipped in. As long as whatever it is has a low water content, the mascarpone and other secret powders will hold down the fort until it’s time to serve. I can also assure you it’s just as good with nothing but a splash of vanilla extract or a scrape of half a bean to flavor it.

Notes:

• So long as you cover and return this straight to the fridge once it’s prepared, the whipped cream should remain stable for about 3 days, possibly longer. If you do take it out and find it’s wept out a bit of moisture, you can briefly hand-whisk it back in before using.

• As I mentioned, you can flavor this with almost anything or nearly nothing. I’d advise against fresh fruit, since the water will seep into the mixture and collapse it, even if you’re using it right away. If you want a fruit flavor, I recommend using a jam that you love. (Bonne Maman makes beautiful ones, and has a line of “intense” jams that are a tad thicker, use less sugar, and are smooth, without any chunks of fruit. I used the strawberry version for this and really loved the effect.) Caramel sauce or chocolate ganache would be easy to add, or even cocoa powder for a more subtle chocolate vibe.

• This makes A LOT of whipped cream. Depending on how you frost your cake, you may have extra left over. I’m hopeless frosting the sides of a cake so I do healthy layer of frosting between and on top, and no one is mad there’s extra. Use it for dipping berries, stone fruit, topping shortcakes or biscuits, or, if there are birthday pancakes or waffles on deck for the next morning, swoop a scoop right on top for a really special treat.

Whipped Mascarpone Cream

Makes about 6 cups

2 cups cold heavy whipping cream

1 cup cold mascarpone cheese

1/2 cup powdered sugar

1 teaspoon vanilla extract or seeds from 1/2 of a vanilla bean

1/2 teaspoon cream of tartar

1/4 teaspoon fine sea salt

1/2 cup fruit jam of choice, caramel sauce, or ganache, plus more if needed (optional)

Food coloring of choice, as needed (optional)

In the bowl of a stand mixer with the whisk attachment, pour the cream and begin whipping at low speed. Whip for 1 minute and increase the speed to medium-high. Whip for 3 minutes, or until the cream is beginning to thicken. Add the mascarpone, powdered sugar, vanilla, cream of tartar, and salt, and slowly bring the mixer back up to medium-high speed. (There may be a moment early on where the mascarpone looks ominous and stubborn, like it won’t whip in. It will! Stay the course.) Whip until the mixture is very lofty and thick and has just about doubled in volume, about 3 to 5 minutes. If you’re adding any flavors or colors, reduce the speed to low and add them with the mixer running. Stop the mixer to check for taste and adjust if needed. Add any additional ingredients here (you might want more sugar or more jam) and incorporate on low speed.

Store the whipped mascarpone cream in an airtight container and refrigerate for up to 3 days before using.

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