Ingredients

• Nonstick vegetable oil spray
• 1 1/4 cups all purpose flour
• 5 tablespoons sugar
• 1/8 teaspoon salt
• 1/2 cup (1 stick) chilled unsalted butter, diced
• 1 large egg, separated
• 2 (or more) teaspoons ice water
• 1/4 cup (1/2 stick) unsalted butter
• 1/2 cup (packed) golden brown sugar
• Pinch of salt
• 1/2 cup heavy whipping cream
• 1/3 cup honey
• 1 cup lightly salted dry-roasted peanuts
• 1 cup powdered sugar
• 1/3 cup creamy (smooth) natural peanut butter (made with only peanuts and salt)
• 2 tablespoons plus 1 to 2 teaspoons milk
• 6 ounces bittersweet chocolate, finely chopped
• 1/2 cup heavy whipping cream
• 3 tablespoons lightly salted dryroasted peanuts, coarsely chopped

Instructions

1. Spray 9-inch square or 10-inch-diameter tart pan with removable bottom with nonstick spray. Blend flour, sugar, and salt in processor 5 seconds. Add butter and blend until coarse crumbs form. Add egg yolk and 2 teaspoons ice water. Blend until moist clumps form, adding more ice water by teaspoonfuls if dry. Gather dough into ball; flatten into square or disk (depending on shape of pan). Wrap and chill 1 hour. DO AHEAD: Can be made 1 day ahead. Keep chilled. Soften slightly at room temperature before rolling out.
2. Roll out dough to 11-to 12-inch square or round. Transfer dough to prepared pan. Cut off all but 1/2 inch of overhang. Fold overhang in, creating double-thick sides. Freeze until firm, about 15 minutes. Preheat oven to 350°F. Bake crust until pale golden, checking every 5 minutes and pressing bottom if bubbling and pressing sides up with back of fork if slipping, about 28 minutes.
3. Beat egg white in small bowl until foamy. Brush some white over hot crust to coat inside. Bake 1 minute longer. Cool on rack. Increase oven temperature to 375°F.
4. For filling: Melt butter in heavy medium saucepan over medium heat. Whisk in brown sugar and salt, then cream and honey. Bring to rolling boil, swirling pan occasionally. Boil 1 minute. Whisk in 1 cup peanuts. Pour filling into crust. Bake tart until filling is bubbling thickly, about 15 minutes. Cool on rack until firm, about 2 hours; freeze 15 minutes. Beat powdered sugar and peanut butter in medium bowl until blended. Gradually beat in 2 tablespoons milk, then more by teaspoonfuls to thin slightly; spread evenly over peanut filling. Refrigerate tart while preparing glaze.
5. Melt butter in heavy medium saucepan over medium heat. Whisk in brown sugar and salt, then cream and honey. Bring to rolling boil, swirling pan occasionally. Boil 1 minute. Whisk in 1 cup peanuts. Pour filling into crust.
6. Bake tart until filling is bubbling thickly, about 15 minutes. Cool on rack until firm, about 2 hours; freeze 15 minutes.
7. Beat powdered sugar and peanut butter in medium bowl until blended. Gradually beat in 2 tablespoons milk, then more by teaspoonfuls to thin slightly; spread evenly over peanut filling. Refrigerate tart while preparing glaze.
8. For ganache glaze: Place chocolate in medium bowl. Bring cream to simmer in small saucepan; pour over chocolate. Whisk until smooth. Spread glaze over tart. Sprinkle chopped peanuts around edge. Chill tart until glaze sets, at least 1 hour. DO AHEAD: Can be made 1 day ahead. Keep chilled. Let stand at room temperature 1 hour before serving. Using tip of small knife, gently loosen crust from pan. Push up pan bottom, releasing tart. Cut square tart in half and cut each half crosswise into 7 or 8 slices or cut round tart into wedges.
9. Place chocolate in medium bowl. Bring cream to simmer in small saucepan; pour over chocolate. Whisk until smooth. Spread glaze over tart. Sprinkle chopped peanuts around edge. Chill tart until glaze sets, at least 1 hour. DO AHEAD: Can be made 1 day ahead. Keep chilled. Let stand at room temperature 1 hour before serving.
10. Using tip of small knife, gently loosen crust from pan. Push up pan bottom, releasing tart. Cut square tart in half and cut each half crosswise into 7 or 8 slices or cut round tart into wedges.