Make Ahead: The lamb broth is best to make the day before you want to make the Scotch broth. If you need to make everything the day before, then cook the barley and split peas separately and add them the next day, as they soak up a lot of broth. Leftovers: Store in an airtight container and place in the fridge for up to 4 days. Freeze: Store in a freezer friendly container and store for up to 1 month. Reheat: When ready to use, thaw in the fridge overnight, add bit more broth (lamb, chicken or beef) and reheat over medium heat until heated through. Adjust seasonings.