1
Toast almonds at 400°F for 4 minutes, shaking after 2 minutes.

2

Cool almonds and then pulverize them with a blender or food processor.

3
In a saucepan, cook the sugar and water on medium heat until the sugar dissolves and the mixture starts to boil, about 3 minutes, stirring constantly.

4
Add pulverized almonds and simmer on low heat, stirring frequently. When mixture is about to boil, remove from heat and cover. Let it sit for a minimum of 3 hours and no more than 12 hours.

5

Strain steeped mixture through three layers of cheesecloth into a bowl, squeezing the cloth as you go.

6
Add orange flower water and vodka, then stir. Funnel into glass jar or bottle.

See more at http://www.seriouseats.com/recipes/2011/11/how-to-make-orgeat-recipe-almond-syrup-for-cocktails.html