Gâteau Basque with Mango Pastry Cream

Instructions

For cake:

1. Place the butter and sugar in the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed until light and fluffy, 2-3 minutes. Add the eggs and egg yolks one at a time. Stop the mixer after each addition to scrape down the bowl.
2. Add the flour, baking powder, lemon zest, and salt all at once. Reduce mixer speed to low, and mix until the dough comes together—do not overmix! The dough will be soft and sticky, that\'s okay.
3. Divide the dough into two discs, with one slightly larger than the other. Wrap each disc in plastic wrap and refrigerate for at least 1 hour.

For mango pastry cream:

1. Put the milk and vanilla in a small saucepan and bring to a simmer over medium-high heat.
2. While milk is heating, put the egg yolks in a separate bowl and add the sugar and mango puree. Whisk well, then add cornstarch and continue to whisk until well combined. Keep a large clean bowl nearby.
3. Temper hot milk into egg/sugar mixture—whisk the egg mixture constantly while slowly pouring in about a cup of the hot milk. Then add everything back to the saucepan, continuing to whisk (this is to prevent the eggs from cooking). Keep whisking (good arm workout!) over medium heat until the mixture is thick and you can see whisk lines clearly forming, which should take a few minutes.
4. Pour into the large clean bowl. Take a sheet of plastic wrap and place directly onto the pastry cream surface - this is to prevent a skin from forming. Refrigerate until the pastry cream comes to room temperature (ideally chilled, but room temp is okay).

For assembly:

1. Spray a 9-inch springform pan with baking spray and line with parchment paper.
2. On a lightly floured surface, roll the larger disk of dough into a 12-inch circle. If it\'s too sticky, just place it directly into the pan, and press it into the bottom and all the way up the sides. Refrigerate for at least 30 minutes.
3. Pour cooled pastry cream into prepared crust, and refrigerate for another least 30 minutes.
4. Roll the smaller dough disc into a 9-inch circle. Place over filling, and crimp the edges so it\'s completely sealed, trimming excess dough as needed. Refrigerate for another 30 minutes.
5. Preheat oven to 400°F.
6. In a small bowl, whisk together 1 tablespoon water and remaining 1 egg. Brush top of dough with egg wash and use a fork to make a criss-cross pattern.
7. Bake for 15 minutes. Reduce oven temperature to 350°F, and bake 20-25 minutes more. Cover the top with foil if it starts to brown too much. Let cake cool completely, then serve at room temperature or preferably, when it\'s chilled.