Joe Jonas is all good to the power of 2!

Joe and gf Sophie Turner were strolling through the SoHo district Thursday in NYC and it's pretty damn clear Joe's delivering the goods. Actually ... more like good, good, and Sophie seems plenty satisfied.

If her smiling face doesn't say it all then just take a closer look ... it's literally written all over her left hand and in plain view -- "Joe Gives Me Da Good Good."

Good work, Joe ... and get it, Sophie!