Imagine an afternoon spent apple picking. You grab a bag of warm apple cider donuts fresh from the farm stand, and lick the sugar from your fingertips. This recipe brings that fall festival vibes in ice cream form. Stripes of cinnamon-spiced vanilla caramel run thick through royal icing-inspired ice cream, dotted with hunks of sugar-and-spice, streusel-topped doughnuts for a pint you’ll be tempted to take home by the dozen.