Preheat the oven to 350 degrees F (175 degrees C).
Combine flour, baking soda, baking powder, and salt in a medium bowl.
Beat brown sugar, butter, evaporated milk, and vanilla extract in a separate bowl until creamy. Beat in egg. Gradually mix in flour mixture. Stir in chocolate chips and pecans. Spoon into balls and place on cookie sheets about 1 1/2 to 2 inches apart.
Bake in the preheated oven until golden brown, about 10 minutes. Let cool for about 2 minutes before serving.