To make the cupcakes I took a box of Butter Pecan mix, added the ingredients on the back of the box plus a 1/2 cup of dulche de leche (you could also use caramel ice cream topping or something along those lines). Once all incorporated fill your cupcake liners with the batter.
For the topping
1 cup chopped walnuts
2 tbsp. sugar
1/3 cup brown sugar
1/4 cup dulche de leche
2 tbsp. butter, cubed
Mix all of the ingredients together with hands to make sure all of the butter is incorporated. Spoon about 1/2 tsp. on top of each cupcake. Bake as instructed on the back of the box. Let cool.
The topping will sink to the bottom due to the extra liquid you added, I thought of using less water in the batter but the extra liquid made them so moist. You can frost with cream cheese icing or top with some dulche de leche. I found they were perfect with nothing on top but the choice is up to you.