1⅔ cups (400 mL) all-purpose flour
3 tbsp (45 mL) granulated sugar
⅔ cup (150 mL) cold unsalted butter, cut in cubes
2 tbsp (30 mL) ice water
1 tsp (5 mL) vanilla extract
½ cup (125 mL) walnut halves or pieces, optional
¾ cup (175 mL) pure maple syrup
½ cup (125 mL) packed brown sugar
2 tbsp (30 mL) unsalted butter, melted
2 tsp (10 mL) vanilla extract
½ cup (125 mL) raisins, optional
2 tsp (10 mL) unflavoured powdered gelatin
1½ cups (375 mL) whipping cream, divided
2 egg yolks
¼ cup (60 mL) pure maple syrup
1 tsp (5 mL) vanilla extract
- For the crust, combine flour and sugar in a bowl. Cut in butter with a pastry blender until in coarse crumbs. Combine ice water and vanilla. Drizzle over flour mixture. Stir with a fork until dough starts to gather. Working gently with your hands, gather into a ball and press into a disc. Wrap and refrigerate for 15 minutes or until slightly chilled.
- Roll out on a lightly floured piece of parchment paper to fit a 10-inch (25 cm) tart pan. Press into pan, pressing any cracks to seal. Trim edge and prick lightly with a fork. Refrigerate for 30 minutes.
- Preheat oven to 375°F (190°C). Line tart shell with parchment paper or foil and fill with rice to weigh pastry down. Place a baking sheet on the bottom rack and bake tart shell on the centre rack for 20 minutes or until edge is dry. Remove rice and paper. Bake for 10–15 minutes longer or until just starting to turn golden brown and firm. Remove from oven and let cool. (Leave oven on and leave baking sheet on bottom rack.)
- If using walnuts, toast on a baking sheet for about 8 minutes or until fragrant and golden. Let cool, then finely chop and set aside.
- Reduce oven to 325°F (160°F). For filling, whisk eggs, maple syrup, sugar, butter and vanilla in a large measuring cup until well blended. Sprinkle raisins in tart shell (if using). Pour filling into cooled shell, stirring to spread raisins evenly as necessary.
- Bake for about 35 minutes or until filling is puffed around edge and just set in centre. Let cool completely in pan on a rack.
- Once tart is cool, prepare the maple mousse. Sprinkle gelatin over 2 tbsp (30 mL) of the cream and let soften for 5 minutes. Set aside ¼ cup (60 mL) of the remaining cream, then refrigerate remaining cream in a mixing bowl.
- Whisk egg yolks in a small bowl until blended. Bring maple syrup to a boil in a small saucepan over medium-high heat. Boil, stirring, for about 3 minutes or until fragrant, slightly darker and slightly reduced. Pour in ¼ cup (60 mL) reserved cream. Remove from heat and stir until bubbles subside. Gradually pour into egg yolks while whisking constantly. Return to saucepan and cook over medium-low heat, whisking constantly, about 3 minutes or until starting to thicken. Stir in gelatin mixture and cook, stirring, for 2 minutes or until gelatin is dissolved. Transfer to a clean bowl and let cool to room temperature, stirring often, about 15 minutes.
- Whip remaining cream in chilled bowl to soft peaks. Fold in vanilla. Stir one-quarter into the cooled egg yolk and gelatin mixture until well blended. Add back to whipped cream in bowl and beat until blended. Fold in walnuts (if using). Spread or pipe mousse on top of tart. Refrigerate until mousse is set, at least 30 minutes or for up to 8 hours. Remove ring from tart pan and place on a plate. Garnish with extra walnut pieces, if desired.