Giovanni Ferrero has expanded his family's company beyond brands like Nutella and built a global powerhouse—especially through big acquisitions in the U.S.

WK Kellogg, the maker of iconic American cereal brands, will be folded into the privately held owner of Nutella and Tic Tacs in a $3.1 billion deal.

The Italian candy maker behind Ferrero Rocher and Nutella is nearing a deal to buy cereal maker WK Kellogg , a source told Reuters, an acquisition that would combine two of the world's best known consumer food makers.