* 1/2 cup sugar
* 1 large egg
* 1/4 cup fresh lemon juice
* 1 1/2 teaspoons finely grated lemon peel
* Pinch of salt
* 3 tablespoons unsalted butter, diced
* 1 cup chilled heavy whipping cream
* 3/4 cup water
* 3/4 cup whole milk
* 3/4 cup (1 1/2 sticks) unsalted butter, diced
* 1/2 teaspoon salt
* 1 1/2 cups sifted all purpose flour (sifted, then measured)
* 6 large eggs, divided
* Robin Eggs malted milk candy (optional)
* 4 ounces high-quality white chocolate (such as Lindt or Perugina), finely chopped
* Special Equipment: Pastry bag with 1/2-inch plain round tip
For lemon-cream filling:
Combine sugar, egg, lemon juice, lemon peel, and pinch of salt in heavy small saucepan; whisk to blend. Add butter. Stir constantly over medium-low heat until curd is hot and thick enough to coat spoon (do not boil), 4 to 5 minutes.
Transfer lemon curd to medium bowl. Using electric mixer, beat cream in another medium bowl until peaks form. Fold whipped cream into curd in 3 additions. Cover and chill filling 1 hour. DO AHEAD: Can be made 2 hours ahead. Keep chilled.
For cream puffs:
Position 1 rack in top third and 1 rack in bottom third of oven and preheat to 425°F. Line 2 large rimmed baking sheets with parchment paper. Bring first 4 ingredients to boil in heavy large saucepan over medium heat, stirring with wooden spoon until butter melts. Add flour all at once and stir vigorously until dough forms and pulls away from sides of pan. Continue to stir until film forms on pan bottom, 1 to 2 minutes longer. Transfer dough to large bowl. Cool 5 minutes, stirring occasionally. Add 1 egg and, still using wooden spoon, beat until blended. Add remaining 5 eggs, 1 at a time, beating until blended after each, then beat until dough is smooth and shiny, 2 to 3 minutes.
Working in batches, transfer dough to pastry bag fitted with 1/2-inch plain round tip. Pipe 1- to 1 1/4-inch mounds, spaced about 2 inches apart, onto prepared baking sheets. Using wet finger, smooth tops of mounds.
Bake puffs 15 minutes. Reverse baking sheets. Reduce oven temperature to 350°F. Continue to bake until puffs are dry, firm, and deep golden brown, 30 to 35 minutes longer. Cool puffs on baking sheets.
Cut each puff horizontally in half; pull out any soft dough. Fill puff bottoms with 1 tablespoon lemon-cream filling. Place egg-shaped candy atop filling, if desired. Press on puff tops to adhere.
Place white chocolate in medium metal bowl. Set bowl over small saucepan of barely simmering water. Stir until chocolate is soft and almost melted. Remove from over water; stir until completely melted and smooth. Using teaspoon, drizzle white chocolate decoratively over each cream puff. Arrange filled puffs on platter. Refrigerate until chocolate glaze sets, at least 15 minutes and up to 3 hours.