1) As Mencken might 2) Deadpan 3) In a deadpan manner 4) In a dry laconic manner 5) In a sardonic way 6) In a straight-faced way 7) With dry humor 8) With sardonic wit 9) With tongue in cheek 10) Without cracking a smile 11) Without humor 
• (adv.) See Dryly.
Dri'ly adverb See Dryly . Thackeray. 
[adv] - with dry humor