Preheat the oven to 180C/350F. Line a large baking sheet with parchment paper.
In a small bowl, whisk together the sugar and cinnamon.
In a large bowl, whisk the egg white until frothy.
Add the almonds to the egg white mixture until fully coated. Add the sugar mixture and mix until combined.
Transfer the almonds onto the lined sheet and bake for 20 minutes, stirring halfway through.
Remove the almonds from the oven and let them cool for 5 minutes before stirring once more to prevent clusters.
Notes
Skillet/Stovetop option: Add the sugar and cinnamon, along with 1 1/4 cups of water, in a saucepan or skillet over medium heat. Let everything simmer until a syrup forms. Add the almonds and mix until combined. Transfer onto a lined sheet to firm up.TO STORE: Leftover candied nuts can be stored in an airtight container at room temperature for up to one month or in the fridge for two months. TO FREEZE: Place almonds in a ziplock bag and store in the freezer for up to six months.