How do you get the Golden Spatula Drumstick Icon?
It was a mission or event reward. Riot's description in the client reads: “This icon will be earned by participating in the CN 8th anniversary engagement event, via the completion of some missions.”
Is the Golden Spatula Drumstick Icon still available?
No. Riot tied the Golden Spatula Drumstick Icon to 2019 (mission reward), and it does not normally bring back past event rewards or bundles.
