1 tablespoon unsalted butter, at room temperature
1/3 cup plus 1 tablespoon granulated sugar
3 extra-large eggs, at room temperature
6 tablespoons all-purpose flour
1 1/2 cups heavy cream
2 teaspoons pure vanilla extract
1 teaspoon grated lemon zest (2 lemons)
1/4 teaspoon kosher salt
2 tablespoons pear brandy (recommended: Poire William)
2 to 3 firm but ripe Bartlett pears
Preheat the oven to 375 degrees F.
Butter a 10 by 3 by 1 1⁄2-inch round baking dish and sprinkle the bottom and sides with 1 tablespoon of the granulated sugar.
Beat the eggs and the 1⁄3 cup of granulated sugar in the bowl of an electric mixer fitted with the paddle attachment on medium-high speed until light and fluffy, about 3 minutes. On low speed, mix in the flour, cream, vanilla extract, lemon zest, salt, and pear brandy. Set aside for 10 minutes.
Meanwhile, peel, quarter, core, and slice the pears. Arrange the slices in a single layer, slightly fanned out, in the baking dish. Pour the batter over the pears and bake until the top is golden brown and the custard is firm, 35 to 40 minutes. Serve warm or at room temperature, sprinkled with confectioners' sugar, and creme fraiche.