“We are delighted to have secured new business with a successful, dynamic and expanding high-street brand,” said DBC business development head Steve Jones.
This year DBC has won contracts to supply Little Chef, worth £12m, and Café Nero Express.
It was bought by Woodward Foodservice in 2006 but the companies are run separately. Brakes has since agreed to buy Woodward but will not be acquiring DBC.
GBK offers a wide range of freshly prepared burgers and has doubled in size in each of the past two years.