Purple powers activate. Avery and Matt cook up some freaky purple mashed potatoes with a side of purple coleslaw and then get artistic when they realize their plates need a little more colour. Lily ventures out to a gelato emporium to sample their rainbow-coloured flavours, learn how gelato is made, and find out if colour can affect a food's taste. Then it's blackberries versus blueberries as our hosts ask which fruit contains the most purple-staining action.