皮肉な笑いを浮かべて彼は私を見つめた。

。

With a sarcastic smile, he stared at me.

Literal

Sarcastic smile [object-を] floating [then-て] he [topic-は] me [object-を] stared.

皮肉な笑い means 'sarcastic/ironic smile.' 浮かべる means 'to float, display (an expression).' 見つめる means 'to stare at.' The te-form links the facial expression to the staring action.