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).
In bowl, combine sugar and cinnamon; set aside.
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. Toss with cinnamon sugar while still warm. Repeat with remaining rice and cinnamon sugar.
Divide puffed rice among 6 bowls. Divide milk evenly among bowls. Drizzle with chocolate sauce and salted caramel sauce.
Top dessert bowls with a generous dollop of whipped cream if desired.
To ensure proper drying, spread the rice evenly in a thin layer with minimal clumping on the baking sheet.