Protein shake is a good option but I’d add some fats to it too, example peanut butter, soya milk, coconut milk.
I think people other think what to break a fast with. It’s doesn’t matter too much, what matters more is the volume of food, keep it low and don’t go crazy on calories, 1k max. Stay after from junk food too and stick to keto/low to moderate carbs.
Your body is in a prime position to refeed and eat after a long fast. Don’t be scared to try stuff other than bone broth etc.