When Mars Chocolate North America announced last year that it will be launching Caramel M&M’S – this spring – many consumers wondered, “What took you so long?”

But as most candy makers and confectioners know, we’re talking caramel here. And as Hank Izzo, v.p. of research and development of parent company Mars Chocolate North America, told CNN Money last year, creating a caramel-filled chocolate, candy-coated lentil isn’t as easy as it sounds.