For the crust:
1 cup all-purpose flour
1/2 teaspoon salt
5 tablespoons cold butter
4 to 5 tablespoons water
For the filling:
1/2 cup butter
1 cup sugar
4 medium pears, peeled, cored and quartered
Step 1: Make the dough
Combine all-purpose flour and salt; cut in cold butter until crumbly. Gradually add 4-5 tablespoons ice water, tossing with a fork until the dough holds together when pressed. Shape into a disk; wrap and refrigerate for 1 hour.
Step 2: Prepare the filling
Preheat oven to 375°F. In a 10-inch cast-iron or other ovenproof skillet, melt butter. Add sugar, stirring until it is liquefied and starts to turn golden brown. Add pears. Cook on medium-high until pears are crisp-tender and caramel is brown, about 10-12 minutes. Remove from the heat.
Step 3: Bake and serve
Roll out the dough to an 11-inch circle; place over pears in the ovenproof skillet, pressing gently to completely cover. Do not flute. Bake until pears are tender and the crust is golden brown, about 30 minutes. Cool 5 minutes before inverting onto a serving plate.