The Green River flavor is part of Chicago's History, dating back to 1919 when Schoenhofen Edelweiss Brewing Company began bottling and selling it. During prohibition it became extremely popuplar.
Since there are so many Chicago St. Patrick's Day Traditions that won't be happening this year. Time Out Chicago Reports: "Eli's Cheesecake and Green River Soda have joined forces to create Eli's Green River Cheesecake, a neon green confection that combines the lime flavor of the Chicago soft drink with lime gelée topping and a butter shortbread cookie crust."
Time Out Chicago also reported, " Catering to those who want to eat something green on St. Patrick's Day, Eli's Green River Cheesecake (which sounds a bit like key lime pie) will be available at Jewel-Osco grocery stores throughout Chicagoland, via the Eli's Cheesecake online shop and through the Eli's Cheesecake bakery (6701 W Forest Preserve Dr). The seven-inch cake will run you about $15 and you should be able to track down a few bottles of Green River to go with it."
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