FREE COLD FOAM: Cold Foam Days at Starbucks take place from May 7 through May 11. Rewards members in the U.S. or Canada can add cold foam to a cold beverage for free.

Starbucks Rewards members are getting a perk with the coffee giants Cold Foam Days which will run from Wednesday to Sunday. Rewards members can redeem the free add-on by applying the coupon in the Starbucks app or by requesting it in-store at participating locations. (Photo by Smith Collection/Gado/Getty Images) Smith Collection/Gado/Getty Images

A writer reviews Starbucks' Brown Sugar Cold Foam for free Cold Foam Days, and shares info on the Reserve Roasteries summer menu with an ube espresso martini.