Arrange the almonds in a single layer on a foil-lined baking dish or in a silicone brownie bite pan. Set aside.

In a heavy saucepan, combine butter, sugar, salt, and vanilla extract. Cook over medium-high heat, stirring constantly until the butter melts and mixture comes to a rolling boil.

Continue boiling and stirring for an additional 5-7 minutes until the candy turns the color of almonds (about 300°F). Pour over the almonds immediately. If using a brownie bite pan, use a small scoop to fill each cavity quickly.

Allow the toffee to cool completely, about 2 hours.

Spread melted chocolate over the cooled toffee and sprinkle with ground walnuts. Allow the chocolate to set before breaking into pieces or popping out of the pan.