Martha Stewart says she had a blast filming a cameo on "The Real Housewives of New York City" reboot ... and it sounds like she's going out on top.

We got Martha in the Big Apple and our photog asked her if we should expect to see her making more appearances ... or if she'll be one-and-done.

Martha says she's probably "one and a half done" ... so it sounds like there's a slim chance she films another scene. Hey, never say never.

TMZ broke the story ... Martha's cameo is filmed and in the can, she appeared alongside her longtime makeup artist Daisy Toye, who's a new cast addition in the upcoming Season 16.

We also asked Martha what her experience was like on 'RHONY' ... and she gives us a rundown on her day on set.

No word when her cameo will air, but it sounds like she's glad she signed on ... at least for a small role.