Cook’s Illustrated first planted the seed of using ground instant tapioca in pie fillings. Cornstarch, the common alternative, is too chalky. Tapioca lends a quiet boost to the flavor, and a delicate texture against the fruit. Tapioca is the preference in all of my fruit pies, except apple, where I use flour. In that one case the mealiness of the flour is somehow exactly right. Otherwise, it’s tapioca for me. In our neighborhood, Williamsburg, instant tapioca is really hard to find. Sometimes C-Town has it, but you just never know. So when I do find it, I grind up as much as I can deal with in my coffee grinder and put it into very clean, very dry, small jars; so it’s ready to go. I really hate having to clean the coffee grinder.
This recipe should be thrown together with whatever late summer ingredients you have around. Swap in extra eggs, cream, or crème fraîche. Ricotta or chevre would be amazing additions. Substitute any seasonal berry or stone fruit.
for the dough
1 cup plus one tablespoon unbleached all-purpose flour
1/2 teaspoon salt
1 tablespoon sugar
1 stick, or eight tablespoons, soft butter
1/4 – 1/3 cup ice water
for the filling
3-4 peaches, washed and sliced into one inch slices
1/3 cup yogurt
1/4 cup sugar
2 tablespoons lime juice
1 tablespoon ground instant tapioca (see explanation above)
dash of nutmeg
dash of lime zest
pinch of salt
In the bowl of a food processor, combine the flour, salt and sugar. Scatter the butter around the bowl and then pulse several times until it’s combined. Turn the processor on and drizzle in the water just until the dough becomes cohesive. Turn out into a bowl or a work surface and form into a flattened disc. Wrap tightly with plastic and chill for an hour or so. Toss the peaches with the lime juice, sugar, salt, nutmeg and tapioca, and let sit at room temperature.
Preheat the oven to 400 degrees. Roll the dough out on a floured piece of parchment. When you have a ten inch round, use the parchment to flip the dough and press into a 9-10 inch tart pan. Fold any overhanging dough into the sides. Cook the dough until it is just cooked through, but still pale, at most 15 minutes. Remove from oven.
Briefly beat the eggs and then fold in the yogurt. Arrange the peaches in the pan slice side down, and then pour the egg and yogurt mixture on top. Sprinkle with lime zest. Cook until the custard edges are bubbly and firm, but before the center is set, roughly 35 minutes. Give the tart a half hour to cool. Serve by itself or with a dollop of whipped cream.