Jason Biggs & Jenny Mollen Enjoy Family Dinner in NYC Amid Separation

Jason Biggs and Jenny Mollen look like they really are on great terms despite their separation ... 'cause the estranged couple just stepped out together for the first time since announcing their split.

The two were spotted in New York City over the weekend, heading out for a family dinner with a larger group ... enjoying good food, good company, and what looked like an easygoing night out together.

Jason and Jenny announced their separation last month after 18 years of marriage, with a rep telling us they were on great terms with zero drama ... and that still appears to be the case ... they appeared totally comfortable in each other's presence on this outing.

At one point Jenny grabbed Jason's arm, but there was no obvious PDA.

It seems they've settled into a new chapter as family, especially with sons Sid, 12, and Lazlo, 8, still at the center of their lives.

Jason and Jenny first met in 2007 while filming "My Best Friend's Girl." Months later they got engaged and then eloped in April 2008.

Jenny caught flak online last week over a since-deleted social media post where she captioned some photos with her son, "Your eldest son will be the most toxic guy you ever date."