I put a forkful of fillet steak in my mouth. [+ of]

我叉了一块无骨牛排放进嘴里。

He lingered over the chocolate cake, letting each forkful slowly dissolve in his mouth.

他细细地品尝巧克力蛋糕，让每一口蛋糕在嘴里慢慢溶化。