In a medium-sized mixing bowl, mix all filling ingredients until fully combined. Set aside.
Preheat oven to 350 F.
In a medium-sized mixing bowl, mix flour, baking powder, baking soda, salt, butter, and syrup until fully combined.
Mix in egg.
Mix in heavy whipping cream.
Fill non-stick or silicone cupcake liners with 1 tablespoon of cupcake batter per liner. If needed, spread batter out with the back of a spoon to fill the whole bottom surface of each liner.
Top cupcake batter with a single layer of nuts.
Top nuts with three tablespoons of filling per cupcake liner. The cupcake liner should be about half full. If you overfill the liners, the cupcake will overflow during baking.
Bake for twenty minutes and remove from oven.
Top each cupcake with pecans so that the pecans come to the top (or just above the top) of each liner.
Drizzle syrup over pecan topping.
Return to oven for another five minutes or until pecans are lightly browned.
Cool cupcakes in the cupcake tins. If you remove them too early, they won't hold their shape.
It is extremely important that you do not overfill these cupcakes. If you fill them too high, they will overflow during baking. I suggest doing a single test cupcake before baking the entire batch to ensure that you have the fill level correct.