boastfully

Turning to Micklin he said boastfully "I'll bet you a hundred dollars you ——s won't hold that meeting tomorrow!"

“I flatter myself I could, too,” said Dunn, but not boastfully.

You just let me manage this, Rowena had declared boastfully.

"Well, when he saw that you were Dacotahs he was frightened," Little Raven said, boastfully.

Subsequently we learned that the raiders were Texans who boastfully declared that they asked no quarter and gave none.