Line an 8x8-inch baking pan with waxed paper. Butter the paper.
Bring maple syrup, heavy cream, and brown sugar to a boil in a saucepan over medium heat. Continue to boil, without stirring, until mixture starts to bubble and registers 240 degrees F (166 degrees C) on a candy thermometer.
Remove from heat. Add butter and salt but do not mix. Let sit until mixture reaches 105 degrees F (41 degrees C).
Add walnuts and vanilla; beat until mixture loses its gloss. Pour into the prepared pan and let cool to room temperature. Cut, wrap, and store in the refrigerator.
recipepes.commaple fudge with maple syrup, recipePT15MPT1H5455 calories