Toast walnuts until fragrant, finely chop and set aside to cool. Beat butter and for 1 minute, scrape bowl, put mixer of low, then add the remaining 6 ingredients. Once combined. Raise speed to medium, beating to combine walnuts
To assemble the Maple Buttercream Candy
Using a scale, portion out 1 oz (28g) amounts, rolling into a rough ball. Freeze for 20 minutes. Shape into a disk flat on top and bottom and round around the sides. Using your pointer finger and thumb creates an even shape. Freeze for a minimum of 2 hours. Once completely chilled, melt finely chopped chocolate in microwave in 20-second intervals (timing for melting depends on voltage of your microwave). Line a baking sheet with foil and spray with baking spray. Place a baking spray greased wire rack on top of foil. Use a fork to dip and shake the chocolate off of the buttercream. Place coated buttercreams on top if wire rack. Put remaining melted chocolate into a pastry bag and drizzle lines over buttercreams.