With the rack in the middle position, preheat the oven to 200°C (400°F). Line two baking sheets with parchment paper.
In a bowl, combine the flour, baking soda and salt. Set aside.
In another bowl, cream the butter and brown sugar. Add the egg and beat until the mixture is smooth. Using a wooden spoon, stir in the dry ingredients and pecans.
For each cookie, with floured hands, shape 30 ml (2 tablespoons) of dough into a ball. Push a cube of maple fudge into the centre and cover completely with dough. Place 8 cookies on each sheet. Bake 1 sheet at a time until the cookies begin turning gold at the edges, about 7 minutes. The cookies will remain very soft in the centre.
On removing the cookies from the oven, use tongs to carefully slide the parchment paper from the baking sheet onto a cool surface. Let the cookies cool to room temperature. Repeat with the remaining dough.