Chipotle Mexican Grill Inc CMG shares are sizzling in Monday’s after-hours session after the company announced an additional $500 million buyback.What Happened: After the market closed on Monday, Chipotle said its board approved an additional$500 million in share repurchases, bringing its total buyback authorization up to $750 million.“This is Chipotle's regular quarterly Board authorization that normally would be announced in its Quarterly Report on Form 10-Q for the third quarter of 2025. Chipotle is ann ...