This isn't really a pie, as the name suggests, but a two-layered sponge cake. It differs from the original Boston Cream Pie in that we use bananas in the batter to make it even richer. Here's a quick cleanup tip: When assembling the cake, place a baking sheet under the wire rack to catch the drips as you pour on the chocolate. Drizzling on the chocolate can get very messy!

Ingredients

• 10 tablespoons (1 1/4 sticks) plus 2 teaspoons unsalted butter, at room temperature
• 2 cups mashed ripe bananas (about 6 medium bananas)
• 1 cup sour cream
• 4 large eggs
• 1 tablespoon pure vanilla extract
• 4 cups cake flour
• 13/4 cups sugar
• 2 teaspoons baking soda
• 1 1/2 teaspoons baking powder
• 1 teaspoon salt
• Pastry Cream, recipe follows
• Chocolate Ganache, recipe follows

Directions

Pastry Cream:

2 cups plus 2 tablespoons heavy cream

1/2 cup plus 3 tablespoons sugar

1/2 vanilla bean, split lengthwise in half and seeds scraped out, seeds and bean reserved

3 large egg yolks

3 1/2 tablespoons cornstarch

Combine 2 cups of the cream, 1/2 cup plus 1 tablespoon of the sugar, and the vanilla bean in a medium saucepan. Bring to a gentle boil over medium heat, whisking to dissolve the sugar. Remove from the heat.

Combine the remaining 2 tablespoons heavy cream, the remaining 1 tablespoon of sugar, the egg yolks, and cornstarch in a medium bowl and whisk until pale yellow. Slowly add 1/2 cup of the hot cream to the egg yolk mixture, whisking constantly until smooth. Add the egg yolk mixture back to the hot cream, and whisk well to combine. Return to medium heat, and cook, stirring constantly with a heavy wooden spoon, until the mixture thickens enough to coat the back of a spoon, about 5 minutes.

Remove from the heat and strain through a fine mesh strainer into a clean container. Cover with plastic wrap, pressing it directly against the surface to prevent a skin from forming. Refrigerate until well chilled, about 4 hours. Whisk until smooth before using.

Chocolate Ganache:

2 cups heavy cream

1 1/4 pounds semi-sweet chocolate, chopped (about 3 1/4 cups)

Scald the cream in a small saucepan over medium heat. Remove from the heat.

Place the chocolate in a heat-proof bowl. Add the hot cream and let sit for 2 minutes, then whisk until smooth. Let cool slightly before pouring on the cake.

Yield: about 4 cups