Chef Michel Roux Jr and drinks expert Kate Goodman return for another series. This looks at how to cook up food that will help everyone's bottom line. We throw £640 million worth of bread in the bin every year, so guest Mary Berry surprises Michel with an ingenious use for stale bread to create fish pie topping which he admits he'd never have thought of himself. Mary is full of tips to reduce waste, including sharing stories of her days as 'freezer correspondent' for a weekly magazine when this bit of kitchen kit was introduced to the UK in the 60s.Kate does a tasting of the ultimate in 'waste not, want not' drinks: grappa - made from the waste product of wine making. It's also known as a 'face changer' and Mary's face is indeed a picture when she tries it! And there is lively debate about whether our food is too cheap.