Line a large baking sheet with a silicone baking mat or parchment paper. Grease the baking mat/parchment paper with butter.

In a nonstick pan, combine sugar, water, vanilla extract, and cinnamon. Bring to a boil over medium heat.

Add almonds. Cook and stir the mixture until the water has evaporated. It will change from liquid to syrup to a stringy consistency and then crystallize onto the almonds. Be sure to stir consistently throughout.

Pour the almonds onto the prepared baking sheet and separate them with forks or a spatula. Let cool for about 15 minutes.

Store almonds in an airtight container.