In a blender, add all of your ingredients except the milk and vanilla. Blend on low speed until your rice, almonds and cinnamon are ground up into smaller pieces (about 1 minute). Now pour the contents from your blender into a large bowl making sure to scrape out any pieces left behind. Now add your vanilla and milk and mix well. Cover the mixture for at least 6 hours but preferably over night to let the flavors come out of the rice, almonds and cinnamon and permeate the liquid. After your horchata mixture has rested, place a sieve with cheese cloth over that over a large bowl. Pour your horchata mixture through this to take out the rice, almonds and pieces of cinnamon. Discard these.;Now the horchata is ready to drink.;;To serve:;I like to have a nice frothy top on my horchata so I pour it into a mason jar, place a lid on it and shake it vigorously until a foamy top forms. Then you fill a glass with a lot of ice and pour your horchata over the ice.;Enjoy!