1 1/4 cups unbleached all purpose flour
1/3 cup powdered sugar
1/4 teaspoon salt
1/2 cup (1 stick) chilled unsalted butter, cut into 1/2-inch cubes
1 tablespoon (or more) ice water
3/4 cup sugar
1/4 cup water
1/3 cup heavy whipping cream
2 tablespoons (1/4 stick) unsalted butter, cut into 1/2-inch cubes
1 teaspoon apple cider vinegar
1/4 teaspoon salt
2/3 cup hazelnuts, toasted
, husked, coarsely chopped
1/3 cup heavy whipping cream
1 1/2 teaspoons instant espresso powder
4 ounces high-quality milk chocolate (such as Lindt, Perugina, or Valrhona), chopped
1 tablespoon unsalted butter
1 tablespoon cacao nibs*
Special equipment: 1 13 3/4 x 4 1/2-inch rectangular tart pan with removable bottom