Pulverize the rice in a blender or spice grinder.
Transfer to a medium-sized bowl and add the almonds, cinnamon, and lime zest.
Stir in 2 ½ cups of hot water; cover and let stand at least 6 hours.
Transfer the mixture to a blender and process for 3-4 minutes, until it is completely smooth.
Add 2 cups of water; blend for another minute. Strain with a damp cheesecloth or a fine sieve.
Add 2 more cups of water and sweeten with sugar to taste. If it is too thick, add more water.
Cover and refrigerate until you’re ready to serve. Stir before serving. Will keep for 5 days in fridge.