08/01/2011 AT 06:00 AM EDT
and hubby Nick Offerman
(of Parks & Recreation
) shared a lovely dinner with Patricia Clarkson
on the patio at West Hollywood's Chateau Marmont
. The trio chatted all night – and Mullally's distinctive laugh rang out over the patio. The ladies were wrapped in scarves and seemed "upbeat and bubbly" during their meal, according to an onlooker. Says the onlooker: "It definitely appeared like they were old pals catching up."