苦虫を噛みつぶしたような顔で、綾乃ちゃんは舌打ちした。

、。

With a face like she'd bitten into a sour bug, Ayano-chan clicked her tongue.

Literal

Bitter-bug [object-を] bit-crushed-[past-た] [like-ような] face [with-で], Ayano-[diminutive-ちゃん] [topic-は] tongue-click did.

苦虫を噛みつぶしたような顔 ('a face as if biting a bitter bug') is a classic set idiom for a very sour, disgusted, scowling expression — as if you'd bitten into a nasty-tasting bug. 舌打ち ('tongue click, tsking') is the disapproving sound. ~たような顔 uses ~たような to form 'a X-like face' where the preceding clause describes the expression.