In a saucepan, combine whole milk, heavy cream, vanilla bean and seeds, 0.67 cups of granulated sugar, cornstarch, and salt.

Cook over medium heat, stirring constantly until the mixture thickens.

In a bowl, whisk egg yolks and slowly add the hot mixture to temper the eggs.

Return to the saucepan and cook until the mixture thickens more, then remove from heat and whisk in cold unsalted butter.

Cover the pastry cream with plastic wrap and chill in the refrigerator.

In another saucepan, combine water, 0.5 cups unsalted butter, 1.5 tablespoons granulated sugar, and 0.5 teaspoon salt.

Bring to a boil and then add all-purpose flour, stirring quickly until it forms a ball.

Remove from heat and let cool slightly before adding eggs one at a time until the mixture is smooth and glossy.

Pipe the choux pastry onto a baking sheet and bake at 400°F (200°C) until golden and puffed.

Let cool completely before filling with the chilled pastry cream.

Dust with confectioner's sugar before serving.