In a large saucepan, bring water, butter, sugar and salt to a boil. Add flour all at once and stir until a smooth ball forms.
Remove from heat and let stand for 5 minutes. Add eggs, one at a time, beating well after each addition. Continue beating until dough is smooth and shiny.
Insert a 3/4-inch round tip into a pastry bag; add dough. Pipe 3-inch strips about 3 inches apart on a greased baking sheet.
Bake at 400F for 25-30 minutes or until golden brown. Remove to wire racks.
Immediately split puffs open; remove tops and set aside. Discard soft dough from inside. Cool puffs.
In a large mixing bowl, beat cream until it begins to thicken. Add sugar and vanilla; beat until stiff peaks form.
In another bowl, mash bananas; gently fold in whipped cream. Spoon into eclairs and replace tops.
In a small bowl, combine the confectioners' sugar, cocoa, butter and vanilla. Add enough water to make a thin glaze and spread over eclairs.
Sprinkle with pecans and serve immediately. Refrigerate leftovers.