Butter an 8×8-inch or 9×9-inch square pan. Line with parchment paper or foil, and butter that; set aside.
In a medium saucepan, combine the sugar, evaporated milk and butter. Bring to a full boil over medium heat. Reduce the heat slightly (no lower than medium-low) and boil for an additional 10 minutes, stirring constantly.
Remove from the heat and stir in the powdered sugar, vanilla extract and maple flavoring. Transfer the mixture to a standing mixer (or use a hand mixer) and beat the fudge on medium speed until thick and glossy – about 3 minutes. Fold in the walnuts and pour the mixture into the prepared pan.
Let the mixture cool to room temperature, then cover tightly and refrigerate overnight. Slice the fudge into 1-inch squares and serve. (Fudge can be stored at room temperature in an airtight container.)
Notes
Makes 50 pieces.
Recipe by DessertedPlanet.com at http://dessertedplanet.com/maple-walnut-fudge/