Teresa Giudice's family time wasn't all fun and games ... 'cause she and her daughter Gia went out for a girls afternoon -- to tour a restaurant they might buy!

The reality teleivison star stepped out with Gia Saturday to check out a restaurant in New Jersey ... and, they admitted it's not just their idea of a fun time -- they're actually thinking about open and Italian restaurant using a bunch of family recipes.

Gia points out her mom has multiple best-selling cookbooks full of recipes the fam could use ... enough for a Cheescake Factory-sized menu!

BTW ... the fact they're considering the new venture isn't a surprise -- TG mentioned it on this season of "House of Villains." But, touring restaurants is a concrete step to making it happens, so don't be surprised if "Teresa's" or whatever they name it is open real soon.

As for her future on "The Real Housewives of New Jersey," Teresa says ya gotta ask Bravo about the new contract ... so, the ball seems to be in the network's court.

We broke the story ... Teresa was not asked to leave 'RHONJ' despite rumors that her tenure was coming to an end. We were told in August no casting decision has been made yet.

Like we said, Teresa's been really open about wanting to cement her family's legacy via food ... recently telling The Daily Dish she imagines all of her girls -- Gia, Gabriella, Audriana and Milania -- will get involved.

Word of advice though ... ya might want to nail down the tables at the restaurant -- we got a feeling fans might try and flip 'em!