Pungent and sweet, balsamic vinegar makes a delicious dressing for the trio of fresh berries that fill these cream puffs. Keep this dessert in mind when you visit the farmers' market and can't resist the berries.
Heat oven to 400°F. Bring water, butter, salt to boil in saucepan over high heat. Add flour all at once; stir until ball forms. Cook, stirring, 1 to 2 minutes.
Transfer dough to bowl. Add eggs, 1 at a time, beating with wooden spoon after each. Continue to beat until shiny and smooth.
Spoon dough into large pastry bag without tip. Pipe 12 puffs (2 inch) onto ungreased baking sheets, 2 inches apart.
Bake in 400°F oven 35 minutes or until puffed and golden. Turn oven off. Let puffs stand in oven 10 minutes, door ajar. Transfer puffs to rack; let cool. (Can be made 2 days ahead; store airtight at room temperature.)
Mix vinegar, sugar, rind in microwave-safe 2-cup measure. Microwave on high 3 to 3-1/2 minutes, until thin syrup; mixture will thicken as it cools. Toss syrup, 1 tablespoon liqueur with berries in bowl just before serving.
Beat cream until foamy. Add sugar and liqueur; beat until soft peaks form.
Halve puffs horizontally; remove wet dough from centers. Spoon 2 tablespoons cream on each bottom, then 1/3 cup topping. Cover with tops.