Glazed Almonds

In a large, heavy sauce pan, melt butter on medium heat. As soon as the butter is completely melted, add sugar and stir thoroughly. Continue warming on medium heat, stirring occasionally until sugar melts (hard crack stage). Add almonds and vanilla and stir continuously, until almonds "pop" or just before sugar burns. Remove from heat and pour mixture on to a cookie sheet, spreading flat. Salt and cool to serve.