In bowl, combine coffee granules, hot water, and vanilla and stir until coffee dissolves.
Place marshmallows in a 2 quart glass measuring cup.
Microwave 1 1/2 to 2 minutes or until marshmallows are melted. Stir until smooth.
Stir the coffee mixture into the melted marshmallows.
Working quickly, add cereal to marshmallow mixture. Stir lightly to coat all the cereal.
With a piece of wax paper, press mixture into a 9x13 pan coated with cooking spray.
Let cool completely, about an hour, before cutting into bars.
