Spanx (yes, that Spanx of shapewear and leggings fame) is currently making such denim. Spanx denim, available in three styles, is like the rest of the company's star products in that it's stretchy ...

Shoppers have been snapping up 'numerous pairs' of 'super comfortable' denim leggings from Next. Many thought they were 'great value for money' and there were six colours to choose from.