Preheat oven to 170ºF. Cook rice according to package directions. Transfer to parchment paper-lined baking sheet; bake for 2 to 2 1/2 hours or until dry to the touch and all the moisture has evaporated. Let cool completely (rice should be dry and hard before frying).
Pour enough oil into large saucepan to come 2 inches up side; heat over medium-high heat until instant-read thermometer reaches 425°F. Add a few grains of cooked rice; if oil is hot enough it will start to puff up instantly.
Working in batches, carefully add 1/2 cup rice to hot oil; fry for 5 to 8 seconds or until puffed. Using small metal wire sieve, carefully transfer rice to paper towel-lined baking sheet. Let cool completely.
Line 9-inch square baking pan with parchment paper; set aside.
In a large saucepan set over medium-low heat, combine chocolate chips, peanut butter and maple syrup; cook, stirring often, for 3 to 5 minutes or until smooth and melted.
Add puffed rice to chocolate mixture, stirring until well combined. Transfer to prepared pan. Refrigerate for 1 to 2 hours or until firm and set. Remove from pan; cut into bars.
Puffed rice can be stored in an airtight container at room temperature for 5 to 7 days.
To ensure proper drying, spread the rice evenly in a thin layer with minimal clumping on the baking sheet.