Combine sugar, milk, corn syrup, and salt in a 2-quart heavy saucepan.

Stir constantly until sugar dissolves and the mixture comes to a boil.

Cook without stirring until the mixture reaches the soft ball stage (234°F).

Remove from heat and add butter without stirring.

Let the mixture cool until lukewarm.

Add vanilla extract.

Beat the mixture until it thickens and becomes creamy.

Stir in the toasted almonds.

Spread the mixture about 1/2 inch thick on a wax paper-lined baking sheet.

Let the bark cool completely before breaking it into pieces.