"Well," he commented nonchalantly, "It's none of my business."
He shrugged nonchalantly, but his gaze rested on her thoughtfully for a few moments before he finished his meal.
She shrugged nonchalantly, snapping a dry vine off and examining it as though unaware of the mockery of his question.
"Supper's ready," she announced nonchalantly.
Pretending you don't care when he mentions that he has two tickets for the hottest show in town, or nonchalantly shrugging when the Cindy Crawford look-a-like says she headed to the local coffee shop "alone".