PREPARATION:

1. Combine 3 cups water and cinnamon sticks in medium saucepan. Cover and bring to a boil over high heat. Reduce heat to medium-low. Simmer 15 minutes. Remove from heat; let cool to temperature of hot tap water. Measure cinnamon water to equal 3 cups, adding additional hot water if needed.
2. Place rice in food processor; process using on/off pulsing action 1 to 2 minutes or until rice is powdery. Add almonds; process until finely ground (mixture will begin to stick together). Remove rice mixture to medium bowl; stir in cinnamon water and cinnamon sticks. Let stand 1 hour or until mixture is thick and rice grains are soft.
3. Remove cinnamon sticks; discard. Pour mixture into food processor. Add remaining 1/2 cup water; process 2 to 4 minutes or until mixture is very creamy. Strain mixture through fine-meshed sieve or several layers of dampened cheesecloth into half-gallon pitcher. Stir in 3 cups cold water, sugar and vanilla; stir until sugar is completely dissolved.
4. To serve, pour over ice cubes, if desired. Garnish with lime wedges, if desired.