Ginger-Lemongrass Choux Pastry

Ingredients

• For the Craquelin:
• 3 1/3 cups cornflakes
• 1/3 cup all-purpose flour
• 5 tablespoons maple sugar
• 1/4 teaspoon fine sea salt
• 1 stick unsalted butter, softened
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• For the Choux Pastry:
• 1 stalk lemongrass, smashed and cut into 1/4-inch pieces
• 1 piece fresh ginger , peeled and cut into 1/4-inch thick slices
• 1 3/4 cups whole milk
• 1/2 cup heavy cream
• 2 1/3 cups all-purpose flour
• 5 tablespoons buttermilk powder
• 2 sticks unstalted butter, sliced
• 1/4 cup granulated sugar
• 3/4 teaspoon fine sea salt
• 9 large eggs

Directions

1. For the Craquelin: Put cornflakes, flour, maple sugar, and salt in a food processor and pulse 5 times to break up cornflakes. Then process mixture until it turns into a fine flour, about 1 minute. With the processor off, add butter. Pulse about 10 times, until the dough forms a ball.
2. On a work surface, lay out 2 large sheets of plastic wrap so they overlap in the middle and form a rectangle roughly 18-by-24 inches. Put dough in the center and cover with 2 more overlapping sheets of plastic wrap. Roll the dough into a roughly 13-by-18-inch rectangle. Transfer plastic wrapped dough onto a baking sheet and refrigerate until it is firm, at least 1 hour and up to 3 days.
3. For the Choux: Put lemongrass, ginger, milk, and heavy cream in a medium saucepan and bring to a simmer over medium heat. Remove from the heat, cover the saucepan, and let infuse for 30 minutes at room temperature.
4. Meanwhile, preheat oven to 325 degrees F. Whisk together flour and buttermilk powder. Strain milk mixture into a clean medium saucepan, discarding ginger and lemongrass. Add butter, sugar, and salt to milk, set over medium heat, and bring to a boil, stirring occasionally. Add flour mixture to milk, and, using a wooden spoon or heatproof spatula, stir together. Continue to cook for 2 minutes, stirring constantly, until mixture forms a soft ball and begins to stick to the bottom of the pot.
5. Remove from heat and transfer to the bowl of a stand mixer fitted with the paddle attachment. Mix on low speed for 5 minutes. With the mixer still running, add eggs one at a time, making sure each egg is fully absorbed before adding the next one. Increase the speed to medium-high and beat for 10 seconds, until the choux pastry is smooth and silky. Transfer choux pastry to a covered container and refrigerate for at least 1 hour and up to 3 days.
6. Using a 1-ounce ice cream scoop or a spoon, place scoops of choux pastry onto non-stick or parchment-lined baking sheets, leaving 2-3 inches of space between them (each mound should be about 2 tablespoons in volume).
7. Using a 1-inch round pastry cutter, stamp out rounds of craquelin. Gather up craquelin scraps, re-roll them, and stamp out more rounds. Top each mound of choux paste with a craquelin round, gently pressing craquelin into the choux with your fingers so that it lies flat and the batter just pushes out around the edges.
8. Bake choux pastry for 45 minutes, then rotate baking sheets, and bake until choux is puffed and golden brown, about 15 minutes longer. Turn oven off, open the door a crack, and let choux puffs stand in the warm oven for 15 minutes. Remove from the oven and transfer to a wire rack to finish cooling completely, about 30 minutes.