Arrange almonds in a single layer on a foil lined baking dish or in a silicone brownie bite pan with 24 bites. Set aside.

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

Continue boiling and stirring for an additional 5 to 7 minutes until candy turns the color of almonds (approximately 300°F). Pour over almonds. Use a small scoop if using a brownie bite pan, and work quickly.

Allow the toffee to cool completely, about 2 hours.

Spread melted chocolate over the cooled toffee. Sprinkle generously with ground walnuts. Let the chocolate set before flipping or cutting into pieces.