Chocolate-on-Chocolate Tart with Maple Almonds

Preparation

1. For crust:

   Step 1

   Pulse cocoa powder, sugar, salt, and 1 1/4 cups flour in a food processor to combine. Add butter; pulse until mixture resembles coarse meal. Beat egg yolk and 3 tablespoons ice water in a small bowl; add to flour mixture and pulse until dough just comes together. Form into a 3/4"-thick disk, wrap tightly in plastic, and chill until firm, at least 2 hours.

   Step 2

   Preheat oven to 350°F. Roll out dough on a lightly floured surface to a 12" round. Transfer to tart pan; lift up edges and let dough slump down into pan, then gently press into edge of pan. Trim dough, leaving about a 1" overhang. Fold in overhang; press to adhere. Prick bottom with a fork. Chill in freezer 15 minutes.

   Step 3

   Line pie with parchment paper or heavy-duty foil, leaving a 1 1/2" overhang. Fill with pie weights or dried beans. Place on a rimmed baking sheet and bake until crust is dry around the edges, about 30 minutes.

   Step 4

   Remove parchment and weights and bake until crust is firm and looks dry all over, 5–10 minutes longer. Transfer pan to a wire rack and let crust cool.

   Step 5

   DO AHEAD: Dough can be made 2 days ahead; keep chilled. Crust can be baked 1 day ahead; store tightly wrapped at room temperature.

2. For maple almonds:

   Step 6

   Preheat oven to 350°F. Toast almonds on a rimmed baking sheet, stirring occasionally, until slightly darkened, 6–8 minutes. Let cool.

   Step 7

   Bring almonds, maple sugar, maple syrup, salt, and 1/4 cup water to a boil in a medium saucepan. Reduce heat and cook, stirring often, until mixture turns mahogany, about 5 minutes.

   Step 8

   Remove pot from heat and stir vigorously until almonds are coated with crystallized sugar (they will look sandy). Spread out on a parchment-lined baking sheet; let cool, then coarsely chop.

   Step 9

   DO AHEAD: Nuts can be candied 2 weeks ahead. Store airtight at room temperature.

3. For filling and assembly:

   Step 10

   Combine chocolate and butter in a large heatproof bowl. Bring cream, honey, and salt to a boil in a small saucepan, whisking to dissolve honey. Pour cream mixture over chocolate mixture; let stand 2 minutes. Whisk until chocolate is melted and mixture is smooth. Pour filling into crust and chill until set, at least 4 hours.

   Step 11

   Top tart with maple almonds just before serving.

   Step 12

   DO AHEAD: Tart can be made 2 days ahead; cover and keep chilled. Bring to room temperature before serving.