Here, a generous measure of salt heightens the seductive buttery flavor of the caramel that tops these rustic tartlets. The result is a deep caramel essence that pairs perfectly with the lemony apples and flaky crust.
For the pie dough:
2 cups (10 oz./315 g.) all-purpose flour
1/2 tsp. kosher salt
1 Tbs. sugar
3/4 cup (6 oz./185 g.) cold unsalted butter, cut into pieces
1/2 cup (4 fl. oz./125 ml.) ice water, plus more if needed
4 apples, preferably Crispin or Pink Lady, peeled, cored and sliced 1/4-inch (6-mm.) thick
Finely grated zest of 1 lemon
1 Tbs. fresh lemon juice
1 1/4 cups (10 oz./315 g.) sugar
1/2 tsp. ground cinnamon
1/2 cup (4 fl. oz./125 ml.) heavy cream
1 Tbs. unsalted butter
3 Tbs. dark rum
In the bowl of a food processor, combine the flour, salt and sugar. Sprinkle the butter over the top and pulse for a few seconds, or just until the butter is slightly broken up into the flour but still in visible pieces. Evenly sprinkle the water over the flour mixture, then process just until the mixture starts to come together. Dump the dough into a large zip-top plastic bag and press into a flat disk. Refrigerate for at least 30 minutes and up to 1 day before using.
Line a baking sheet with parchment paper. In a large bowl, toss together the apples, lemon zest, lemon juice, 1/4 cup (2 oz./60 g.) sugar, the cinnamon and a pinch of salt.
Transfer the dough to a lightly floured work surface and cut into 6 equal pieces. Roll each piece into a round about 1/8 inch (3 mm.) thick. Transfer the dough rounds to the prepared baking sheet, spacing them evenly.
Divide the apples between the dough rounds, spreading them into an even layer and leaving a 1-inch (2.5-cm.) border of dough uncovered along the edge. Fold the edge of the dough up and over the apples, loosely pleating the dough and leaving the galettes uncovered in the center. Refrigerate the galettes for about 30 minutes.
Preheat the oven to 400°F (200°C). Bake the galettes until the crust is golden brown and the apples are tender, about 40 minutes. Let cool on the baking sheet on a wire rack.
In a saucepan, combine the remaining 1 cup (8 oz./250 g.) sugar and 3 tablespoons water. Cover and bring to a simmer over medium heat. Once the sugar starts to melt, uncover and swirl the pan gently until the sugar is dissolved, about 5 minutes. Simmer, uncovered, until the sugar turns deep caramel brown, 3-5 minutes. Remove from the heat, add the cream (the caramel will bubble vigorously), and whisk until smooth. Whisk in the butter, rum and 1/2 teaspoon salt. Let cool slightly. Drizzle the galettes with the caramel and serve. Serves 6.