A.T. Robertson Commentary Mark 6:25

"And she came in straightway with haste unto the king, and asked, saying, I will that thou forthwith give me on a platter the head of John the Baptist." — Mark 6:25 (ASV)

Straightway with haste (ευθυς μετα σπουδης). Before the king's rash mood passed and while he was still under the spell of the dancing princess. Herodias knew her game well. See on Mt 14:8f.