Preheat oven to 350ºF and line a large baking sheet with parchment. Place butter, sugar and cinnamon in a small bowl and cook in microwave on high for 1 minute, until butter has melted. Stir to combine. Place almonds in a small bowl; pour butter mixture over, tossing to coat. Spread almonds on baking sheet. Bake for 10 minutes, stirring halfway through. Let cool on baking sheet on a wire rack for 30 minutes.
Line a second baking sheet with parchment and place in freezer. Let ice cream stand at room temperature 15 minutes to soften. Pulse almond mixture, cornflakes and salt in food processor until mixture resembles coarse crumbs. Transfer mixture to a shallow dish.
Scoop ice cream into balls using a 1 1/4-inch scoop. Roll in almond mixture, gently pressing onto balls. Arrange on baking sheet in freezer. Freeze truffles for at least 30 minutes or up to 24 hours.