Cut orange into 8 pieces. Put cut up orange, yes the whole thing!, orange juice, egg and oil in blender. Blend until smooth. Add flour, sugar, baking powder, baking soda and salt. Blend. Add raisins and nuts (if so desired). Blend just until mixed. Pour into muffin tins and bake at 375F for 15 to 20 minutes. Makes 16 medium muffins.