1. Preheat oven to 400°. Stir together flour and sugar.
2. Bring butter and 3/4 cup water to a boil in a 3-qt. saucepan over medium-high heat, stirring occasionally. Immediately remove from heat, and quickly stir in flour mixture all at once. Beat with a wooden spoon until mixture is smooth and leaves sides of pan, forming a ball of dough. Gradually add eggs, beating until mixture is smooth and glossy.
3. Drop dough by rounded tablespoonfuls onto a parchment paper-lined baking sheet.
4. Bake at 400° for 20 minutes or until puffy and golden brown. Remove from oven to a wire rack. Pierce 1 side of each cream puff with a knife to allow steam to escape. Cool completely on baking sheet (about 20 minutes).
5. Cut each cream puff in half horizontally. Dollop coffee ice cream onto bottom halves; top with remaining halves. Cover and chill until ready to serve. Drizzle with hot fudge topping just before serving.