One unclued light is the name of a drink which can be measured into three ingredients. Each ingredient has three definitions among the other unclued lights; unchecked letters of the nine lights in question are supplied by the puzzle’s title.

Across

1 Changing tack, see, I perform on rink? (8, hyphened)
8 Total power in reservoir (4)
12 Contemptuous expression in silence covered by hand (5)
14 Commend arrangement of test run (7)
16 Corridor without a key? (4)
18 Comedian Eddie’s last letter (6)
22 Allegation people inside prevent (8)
23 Intermingle in action in large public buildings (7)
25 Information in addition giving species of penguin (6)
27 Road...