Microwave water and coffee in a 1-cup glass measure at HIGH 1 to 2 minutes.
Combine coffee, flour, soda, salt, brown sugar, egg, oil, and vanilla.
Spread batter in a greased 12- x 8-inch glass baking dish.
Sprinkle nuts and chocolate morsels over mixture.
Microwave at LOW 7 to 8 minutes.
Rotate dish 1/2 turn.
Microwave at HIGH 3 to 4 minutes.
Cut into bars.