1. Preheat oven to 425°. Bring first 3 ingredients and 1/2 cup water to a rolling boil in a 3-qt. saucepan over medium heat; cook, stirring constantly, 1 minute. Add flour all at once, and beat vigorously with a wooden spoon 1 minute or until smooth and pulls away from sides of pan, forming a ball of dough. Remove from heat, and let stand 5 minutes.
2. Transfer dough to bowl of a heavy-duty electric stand mixer. Add eggs, 1 at a time, beating at medium speed until well blended after each addition. (If dough separates, don't worry--it will come back together.) Add Gruyère cheese and next 3 ingredients; beat at high speed 3 minutes or until dough is smooth and glossy. Drop by rounded teaspoonfuls 2 inches apart onto 2 parchment paper-lined baking sheets.
3. Reduce oven temperature to 375°, and bake gougères 10 to 12 minutes, placing 1 baking sheet on middle oven rack and other on lower oven rack. Switch baking sheets, and bake 4 to 6 more minutes or until golden brown. Cool on baking sheets 5 minutes. Repeat procedure with remaining dough.
Make-Ahead Tip: You can make gougères ahead and freeze up to 3 months. To reheat: Place frozen gougères on baking sheets, cover lightly with foil, and bake at 350° for 10 to 15 minutes or until warm.