Prepare the Ingredients: Slice the orange, lemon, and apple into thin rounds. Break the cinnamon sticks in half if desired.
Fill the Pot with Water: Fill a medium-sized pot halfway with water and place it on the stove over medium heat.
Add the Ingredients: Once the water starts to warm up, add the sliced fruits, cinnamon sticks, bay leaves, star anise, cloves, and rosemary sprig to the pot.
Bring to a Simmer: Allow the mixture to come to a gentle simmer. This should take about 5-10 minutes.
Reduce Heat and Simmer: Once it’s simmering, reduce the heat to low. Let the pot simmer for at least 2 hours. Keep an eye on the water level, adding more if it gets too low.