True to the splendid original except for these deviations: the labneh is increased from 12 to 16 ounces; the sugar is decreased, ever so slightly, by two tablespoons. (Depending on the tang of your labneh, you may want more or less sugar.) Medrich also moisture-proofs the crust by brushing it with a beaten egg yolk (and a pinch of salt) after it prebakes. When I make the tart, I skip this step, but if you want to follow it, simply return the tart to the oven for a minute after brushing to set the egg yolk. —Nicholas Day
Preheat the oven to 350. Find your tart pan (9 and 1/2 inch with a removable bottom)
In a bowl, combine the butter with the sugar, vanilla, and salt. Add the flour and mix just until well blended. (If the dough is too soft, let it sit for several minutes.) Press the dough evenly over the bottom and sides of the tart pan; there will be just enough for a thin layer. Place the pan on a cookie sheet.
Bake until the crust is a deep, golden brown, 20-25 minutes. If the dough begins to inflate after about 15 minutes, press it down with the back of a fork and prick it. When the crust is finished, remove it from the oven and lower the heat to 300.
While the crust is in the oven, make the filling, whisking together in this order: the eggs with the sugar, salt, and vanilla. Then whisk in the labneh.
Pour the filling into the hot crust, spreading it evenly. Bake until the filling is set around the edges but quivers in the middle, about 15 to 20 minutes. This is crucial: check it several times in the last few minutes; be careful not to overbake. Cool on a rack; if not serving within three hours, refrigerate.