Don't oversteep: 5 minutes is the sweet spot. Past 7 minutes, the tea turns bitter. Shaking isn't optional: It creates the froth and chills everything evenly. Taste the syrup first: Use real vanilla extract or a bean — imitation vanilla will make it taste like a candle. Batch it: For multiple servings, steep 8 tea bags in 2 cups boiling water, make 2 cups syrup, and shake individually for best foam.