In a medium bowl, stir together butter, brown sugar, syrup, cinnamon and pecans. Put the filling into a heavy duty baggie and set aside.
In a medium bowl, whisk together the flour, baking powder and salt. Whisk in milk, egg and oil just until moistened. Batter will have a few lumps. Let batter rest for 10 to 20 minutes.
Gently stir batter. Dampen one end of a piece of cheesecloth with oil. Wipe the oil soaked end across the surface of the griddle. Use an ice cream scoop or 1/3 cup measuring cup to add the batter to the griddle
Snip off one end of the baggie of cinnamon-pecan filling. Squeeze the filling on top of the pancake batter in a swirl pattern or using a small spoon sprinkle the cinnamon-pecan filling on batter. Cook the pancakes 2 to 3 minutes or until bubbles on the surface begin popping.
Gently flip the pancake over and cook an additional 2 to 3 minutes or until golden brown. Serve with maple syrup and butter.