For the milk chocolate chantilly
225g Guittard Milk Chocolate Baking Wafers
720ml heavy whipping cream
1 Tbsp light corn syrup
1 Tbsp honey
75g malted milk powder
For the tart shell
90g almond flour
120g pastry flour
50g Guittard Cocoa Rouge (Dutch processed unsweetened cocoa powder)
Pinch of salt
220g unsalted butter, at room temperature
130g granulated sugar
5 egg yolks
For the roasted banana marmalade
2 ripe bananas
2 Tbsp unsalted butter, cut into small cubes
1 vanilla bean
Juice from 1 orange
70g raw or turbinado sugar
For the filling
200g Guittard Bittersweet Chocolate Baking Wafers
3 Tbsp plus 2 tsp whole milk
80 ml heavy whipping cream
2 Tbsp unsalted butter, at room temperature
1 large egg
To make the milk chocolate chantilly
1 Place the milk chocolate in a large heatproof bowl. Set aside.
2 In a medium saucepan, combine 240ml of the cream, the corn syrup, honey, and malted milk powder and bring to a boil, stirring frequently. Pour the hot cream mixture over the milk chocolate, and let sit for 5 minutes. Then whisk the chocolate mixture until smooth. Add the remaining 480ml cream and whisk until just combined. Place plastic wrap directly on the surface of the chocolate mixture and refrigerate for at least 30 minutes, or up to overnight.
To make the tart shell
1 In a small bowl, sift together the almond flour, pastry flour, cocoa powder, and salt. Set aside.
2 In a large bowl using a hand mixer, beat together the butter and granulated sugar until light and fluffy, about 3 minutes. Add the egg yolks and beat until smooth. Gradually add the flour mixture and beat until just combined.
3 Form the dough into a disk and wrap tightly with plastic wrap. Chill the dough in the refrigerator for at least 1 hour, or up to 4 days.
4 Preheat the oven to 325°F/165°C. Set aside a 9‑in tart pan.
5 On a lightly floured work surface, roll out the chilled dough to a 10‑in round, dusting with more flour as needed to keep it from sticking. If the dough gets too sticky, put it back in the refrigerator for 15 minutes and add more flour to your work surface. Roll the round of dough onto the rolling pin and carefully unroll the dough onto the tart pan. Press the dough down into the bottom of the pan and up the sides. Using a fork, poke holes into the dough to keep it from puffing up too much while baking.
6 Bake for 6 to 8 minutes, or until the dough is puffed and slightly set around the edges. It will still look a little doughy in the centre, but it will set as it cools. Let cool completely on a wire rack.
To make the roasted banana marmalade
1 Raise the oven temperature to 400°F/ 200°C.
2 Peel and cut the bananas into chunks and place the banana pieces and butter in an 8-by-11‑in baking dish. Put the vanilla bean seeds and pod, orange juice, and raw sugar in the baking dish. Roast in the oven for 20 minutes, stirring as needed.
3 Remove the baking dish from the oven and let cool for 30 minutes. Remove the vanilla bean pod from the mixture and discard. Pour the rest of the mixture into the bowl of a food processor (or blender) and pulse until smooth, about 1 minute.
4 Set aside.
To make the filling
1 Place the bittersweet chocolate wafers in a medium heatproof bowl. Set aside.
2 In a medium saucepan, bring the milk and cream to a boil. Pour the milk mixture over the chocolate and let sit for 5 minutes, then whisk until the chocolate mixture is smooth. Pour the chocolate mixture, butter, and egg into a blender and blend until smooth.
3 Preheat the oven to 200°F/ 95°C.
4 Pour the banana marmalade into the cooled tart shell, spreading it to the edges. Top with the chocolate filling, also spreading it to the edges.
5 Bake for 20 to 30 minutes, or until the top is set. Let cool at room temperature for about 1 hour.
6 Remove the chantilly from the refrigerator and beat in a stand mixer fitted with the whisk attachment (or in the bowl in which it was refrigerated, using a hand mixer fitted with the whisk beaters) on low speed until light and airy, about 3 minutes. Spread or pipe the chantilly on the top of the tart. Serve this the same day you make it, because the fillings will make the crust soggy if it sits for longer than 1 day. Store in the refrigerator in a covered cake carrier or wrapped with plastic wrap.
Fully bake the sweet dough shell and let it cool before pouring in the filling, and then bake the tart in a low oven—just 200°F/ 95°C. You can watch as the transformation takes place: The filling lifts just slightly as it bakes. I think of this tart as elevated ganache set on a perfect platform.
Recipe from Guittard Chocolate Cookbook by Amy Guittard, published by Chronicle Books (£15.99)
Image credit: © Antonis Achilleos