Follow directions on the King Arthur Muffin mix to make muffins, then add 1/4 cup of lemon curd to the muffin mix.
Bake as directed. Allow to cool completely.
Dig out a small hole in the top of each muffin and fill with lemon curd.
Sprinkle suger over the edges of the muffin tops.
Sprinkle grated lemon rind over the lemon curd. Serve and enjoy!