In a large bowl, combine the flour, sugar, baking powder, baking soda and salt. In a small bowl, beat the yogurt, egg, butter, lemon peel and lemon juice until smooth; stir into dry ingredients just until moistened. Fold in the coconut.
Fill paper-lined muffin cups two-thirds full. Bake at 400° for 18-22 minutes or until golden brown and toothpick inserted near the center comes out clean. Cool for 5 minutes before removing from pan to a wire rack.
In a saucepan, combine the lemon juice and sugar; cook and stir over medium heat until sugar is dissolved. Stir in coconut. Using a toothpick, poke 6-8 holes in each muffin. Spoon the coconut mixture over muffins. Serve warm or cool to room temperature. Yield: 1 dozen.