Troubleshooting A Pastry-Cream Crisis

Photo from recipepieces.blogspot.com

When Melissa wrote in about her pastry cream crisis, I felt her pain. I had just had the same experience: Hours before 25 guests were to arrive at my house for a pie social, I awoke to find that the lovely pastry cream that had set up so nicely in the refrigerator at bedtime had turned into a pourable custard.

This meant that instead of enjoying nicely formed slices of honey-vanilla pie with gingersnap crust, my guests were about to face a custard flood when they tried to cut themselves a slice of pie. Aarrrgh! What to do?

Unable to reach my pastry-school-graduate friend in California for a quick crisis consultation, I took to desperate improvisation. First, I dumped the whole batch back into the saucepan, and turned up a medium flame under it, because I knew I would at least have to try re-cooking it. I held back two half-cupfuls of the cream, though, putting each in a separate “rescue” bowl.

I made a cornstarch-and-water slurry and stirred it into one of the rescue bowls. Turning to the other, I sprinkled a half-teaspoon or so of powdered gelatin over the surface of the pastry cream and let it soften for about 10 minutes.

By now, the main saucepan of troubled pastry cream was heating up. I reintroduced both rescue batches–with their hopeful ingredients of cornstarch and gelatin–into the main batch, and kept stirring (and praying) as the heat rose and the time for my company’s arrival drew nearer.

Whatever transgressions I have committed in my life were somehow overlooked by the Pastry Gods on that day: the cream started emitting steam, and gave off that nice thick blurp that it’s supposed to when it wants to show you that it’s done. I poured it through a sieve into a clean bowl and pressed plastic wrap onto the surface.

I put it in the fridge, and after a few hours–we’re talking less than an hour before my guests were due–it showed itself to be creamy and firm enough to hold its shape when sliced. I would have burst into tears of gratitude, but I was waaayyy too busy getting myself and my dining room ready. The honey-vanilla filling went into the gingersnap crust, received an artful drizzle of honey on top, and my crisis was defused. (You can understand now why this pie social has not one single photo to document it; panic–and then relief–trumped picture-taking. Sorry.)

So what the hell happened to make my pastry cream turn from a full-bodied object of love into an embarrassing, runny mess? I wish I could tell you that I had an answer.

Photo from heidibakes.blogspot.com

The run-up to making the filling had been marked by slightly obsessive recipe comparison. I kid you not: I even made a chart, for crying out loud, of a half-dozen or so chefs’ pastry cream recipes so I could quickly compare how much of the key ingredients each uses.

I checked the recipe of piemaker extraordinaire Ron Silver, who owns Bubby’s in New York City; I consulted the recipe in baking guru Rose Levy Beranbaum’s Pie and Pastry Bible; I reviewed Chef Claude Perdriolat’s recipe from my pastry techniques class at L’Academie de Cuisine, and I studied the formula from the Tartine Bakery’s cookbook, which I worship, since that San Francisco shrine makes some of the most breathtaking desserts I’ve ever had. I also checked the recipe in my Williams Sonoma Baking Essentials cookbook.

My little chart showed some intriguing variations among the very few ingredients needed for pastry cream (milk, eggs, cornstarch and sugar, with a little salt and vanilla).

All the recipes fell in the same range for milk: right around 2 cups. Some used half-and-half, or a combination of cream and half-and-half, or just plain whole milk. But for the dairy component, we’re talking 2 cups.

Sugar varied: most recipes called for a half-cup, though Chef Claude tilted sweet, with a full cup of sugar.

Eggs varied a bit, too: most recipes used just yolks–4-6 yolks. Rose used two whole eggs, and Tartine gave us a choice of 2 whole eggs or 4 yolks.

The cornstarch amounts ranged from 3 Tbsp. to 5 Tbsp.

And the technique was always the same: As your dairy heats in a saucepan over medium-high heat, whisk the yolks or eggs together in a bowl until they are light. (Some chefs like to put a bit of the sugar into the milk; Some keep it all for the egg mixture.) As the milk gives off steam, slowly drizzle some (or all) of it into the egg-sugar mixture, whisking constantly to keep the eggs from cooking.

When the hot milk has tempered the eggs, pour the egg-sugar mixture back into the saucepan with the rest of the milk and cook the mixture over medium-high heat until it thickens and reaches that just-boiling stage where it gives off a thick blurp. Cook it just a minute or two more, checking that the cornstarchy taste is gone and the cream starts to look shiny. It should be very thick.

Pour the pastry cream through a sieve into a clean bowl. Some chefs stir in some unsalted butter here; some don’t. But they all then put a sheet of plastic wrap directly onto the surface of the pastry cream and chill it.

And all of them, except me, I’m presuming, get a nice, thick, rich custard that holds its shape. Just look at this fetching photo from respected pastry blogger BrownEyedBaker (and her accompanying recipe for banana cupcakes with pastry cream is worth a look, too).

photo from nellienest.com

So which recipe did I use when I experienced my spectacular pastry-cream failure? It was Tartine’s recipe. Which is why I know for a fact that it wasn’t the ingredients, but something I did with them, that went wrong.

Tartine’s calls for 2 cups of whole milk, 1/4 teaspoon of salt and a split vanilla bean, with its seeds, in a saucepan over medium-high heat. In a bowl, whisk together 3 tablespoons of cornstarch (4 if you want it firmer, such as for a cream pie filling) and 1/2 cup sugar. Whisk 2 whole eggs (or 4 yolks if you like a richer pastry cream) into the sugar and cornstarch.

When the milk verges on boiling, remove the vanilla bean and drizzle about one-third of the liquid into the egg mixture, whisking constantly. Pour the tempered eggs back into the milk mixture in the saucepan and cook over medium heat, whisking as it thickens. You want to bring the cream barely to a boil, so it emits “a few slow bubbles,” as Tartine pastry chef Elisabeth Prueitt says, but you have to be careful not to let the cream boil vigorously or you could curdle it. It should be the thickness of lightly whipped cream, she writes.

Pour the pastry cream through a sieve into a clean bowl. Prueitt calls for the addition of 4 tablespoons of unsalted butter, cut into 1-tablespoon-size pieces, and mixed in one at a time, when each is thoroughly incorporated. Then plastic wrap is pressed onto the surface of the cream and it is chilled.

I don’t know where exactly I went wrong in this process; I did not use the butter at the end, but neither does Chef Claude when he makes his pastry cream, and it comes out quite firm. So firm, in fact, that I opted for Tartine’s recipe because I wanted my pie filling to be a tad softer than Chef Claude’s pastry cream (his uses 2 c. milk and 4 yolks, but ups the cornstarch to 5 Tbsp.).

I did, however, substitute honey for some of the sugar, according to one recipe I found in my searching. A-ha, you might yell, that is where you went wrong! But no, it’s not. Because I have made other pastry cream recipes–pure, without honey–and run into this same runniness problem. And I have made them and had the cream stay just right.

Not a satisfying post, I know; I still toss and turn about this at night. But in the spirit of full disclosure and collaborative problem-solving, CurvyMama wants to get it all out there and see if anyone has suggestions.

The pastry cream challenge commences!