Combine the blackberries, sugar and chopped mint in a large bowl and mash with a potato masher or wooden spoon; let sit while making the tea.
While the blackberries are macerating, bring 1 1/2 quarts cold water to a boil in a medium saucepan. Remove from the heat, add the tea bags and let steep for about 3 minutes. Remove the tea bags and pour the tea over the blackberry mixture. Let the mixture sit at room temperature for at least 1 hour to let the flavors meld.
Pour the mixture through a strainer into a pitcher, pressing on the solids. Cover and refrigerate until cold, at least 2 hours. (You can also pour the mixture into a bowl set over an ice bath to cool it faster.)
Serve the blackberry tea over ice in tall glasses and float a shot of bourbon on top of each. Garnish with fresh mint sprigs (like a mint julep).
Photograph by Lisa Shin
Recipe courtesy Bobby Flay for Food Network Magazine