Mix starter, sugar, egg, and salt in a bowl, set aside. Melt butter in a pan then add milk and warm until 100-110°F.
Add milk to bowl of starter. Add half the flour, then dried fruit and nuts, and mix well.
Add remaining flour. Dough will be sticky/wet right now, don't be alarmed. The dried fruit will soak up excess moisture.
Let rest for 20-3o minutes before kneading gently with wet hands.
Let rise until doubled, about 6-10 hours, and then shape into two logs and place on a lined baking sheet.
Let rise until about 1.5x original size, which will take a few hours. It always takes longer than you think to rise the second time, especially with mix-ins.
Slash the loaves and bake at 375°F for 20 minutes. Rotate the tray and bake another 20 minutes or until it's gently browned and internal temp with an instant read thermometer says 180°F or higher.
Let cool until just warm, then mix up your icing. You want it to be nice and thick but still pourable. Drizzle it all over, slice, and enjoy!