In a medium-sized bowl, combine the sweetened condensed milk, egg yolks (you can save the the whites for another use!), lime juice, and coconut extract. Whisk together until completely incorporated and smooth. Pour the filling into the cooled pie crust and bake for 15 minutes. (The filling won't be completely set, but will after cooling.) Chill the pie in the refrigerator for at least 6 hours, but overnight if possible.