Warren Buffett’s favourite banker is investing in a $US7.5 billion deal for Panera Bread.

On Wednesday, JAB Holdings, which owns Krispy Kreme, Keurig, and Caribou Coffee, announced a $US7.5 billion deal for US bakery chain Panera Bread Co.

JAB said it is buying Panera through JAB BV, an investment vehicle that is made up of JAB Holding, and JAB Consumer Fund, a fund “backed by a group of like-minded, long-term oriented investors.”

In addition, “entities affiliated with BDT Capital Partners are also investing alongside JAB BV.”

BDT Capital is a firm set up by Byron Trott, a former Goldman Sachs banker. It’s not the first time BDT Capital has worked with JAB. In May 2016, BDT advised JAB on its acquisition of Krispy Kreme Doughnuts for $US1.3 billion, according to data from Thomson Reuters.

Byron Trott is perhaps best known on Wall Street as Warren Buffett’s favourite banker. In 2004, Buffett mentioned him by name in a letter to Berkshire Hathaway investors.

“He understands Berkshire far better than any investment bank with whom we have talked and — it hurts me to say this — earns his fee,” Buffett said.

The firm recently advised Mars Inc., the maker of candy and pet food, on its $US9.1 billion deal to buy the animal hospital company VCA Inc. That deal followed Mars’ acquisition of Wrigley, the chewing gum company. In October, Mars took full control of Wrigley after it bought Warren Buffett’s stake in the company.

Buffett originally teamed up with Mars to buy Wrigley for $US23 billion in 2008. Trott brought Buffett into the deal, with the billionaire investor putting $US6.5 billion of his own money into the transaction.

Trott told Fortune magazine in 2014 that his company works only with “billionaires with businesses.”

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