Step 1

Preheat oven to 375°F. Line 2 large rimmed baking sheets with parchment paper. Bring milk, butter, and salt to boil in heavy large saucepan over medium-high heat, stirring until butter melts. Add flour all at once. Reduce heat to medium and stir with wooden spoon until dough forms ball and some batter films bottom of pan thickly, about 4 minutes. Transfer dough to medium bowl and cool 5 minutes. Using electric mixer, beat in eggs and yolks 1 at a time.

Step 2

Drop dough by generous tablespoonfuls 3 inches apart onto baking sheets, making about 24 puffs. Smooth tops with wet fingertips.

Step 3

Bake puffs 15 minutes. Reverse sheets and bake puffs until deep golden, about 10 minutes longer. Make small slit in side of each puff. Return to oven, turn off heat, and let dry 15 minutes. (Can be made 6 hours ahead. Let stand at room temperature.)

Step 4

Stir mango and sour cream in medium bowl to blend. Beat whipping cream and 1/2 cup powdered sugar in large bowl until peaks form. Fold whipped cream into mango mixture. Cover bowl; refrigerate filling at least 30 minutes and up to 3 hours.

Step 5

Cut cream puffs horizontally in half. Spoon heaping tablespoon filling into each bottom half; cover with tops. Sift remaining 1/2 cup powdered sugar over.

Step 6

Divide cream puffs among 8 plates. Spoon sauce onto plates and serve.