Preheat oven to 350F degrees. Place 9 cupcake paper liners into regular muffin pan and spray each of the liners with nonstick cooking spray.
In a bowl, combine the flour, brown sugar and pecans until mixed well.
In a separate bowl, beat the eggs until foamy and then add melted butter. Stir well.
Combine the egg mixture with the flour mixture. Stir until moistened.
Spoon the batter into the muffin cups. You will need to fill them to almost full. There is no leavening agent (like baking powder or baking soda) in these so they won't rise up at all.
Bake for about 20-25 minutes (it took closer to the 25 minute mark in my oven.) Optional: Around the 15 minute mark, pull them out and sprinkle with chopped pecans or place one pecan half on each one, then put them back into the oven to finish baking. (This is just for aesthetics and not necessary).
Bake until a toothpick inserted into the middle comes out clean.
You can also make these into mini-muffins. Just decrease the cooking time by about 5 minutes or so.