I know you've heard of pain de tradition (artisanal baguettes) and there's even saucisson de tradition. In France the word 'tradition' has special cachet, meaning done the old way, made by hand as opposed to industrially-made and is highly prized and sought after.
I'm making up the term (I think) 'patisserie de tradition' so you can recognize the ingredients of an old-fashioned patisserie/boulangerie tout de suite. For one thing they often have brightly colored awnings. No patisserie is more traditional than Maison Stohrer (depuis 1730) on rue Montorgueil. You can't go wrong in here.
Any patisserie de tradition worth its salt will have paintings on glass for sure.
Lots of gold scrolls and decorative motifs.
Plus the essential wheat sower (often an attractive femme) and a windmill or two.
Highly decorative street signs are de rigueur.
And often figurative and silhouetted.
Hand writing on the windows more than likely announcing a prize won for the best baguette or croissant is to be taken note of svp.
Inside look for painting on the walls. There will be starlings, cupids and all kinds of glorious oldie-worldie elements.
Look for FAB decorative tile work.
Old photographs of workers always make my heart go pitter-patter in patisserie traditionnelles.
Natch they will have Macarons. Like who doesn't these days in Paris?
But for sure they will still have the old-fashioned big-as-your-head meringues that were my 1st Parisian love before the macaron came along to steal my heart.
Don't worry. There will be plenty of gorge pastries to gobble up along with the classic madeleines, financiers, chouquettes.
More hand printing on the porte etiquettes. Those charming sign posts in every patisserie in France.
Little French girls haven't changed much thank goodness.
Do not be surprised to hear at the cash register,
"J'pas la monnaie" (I don't have change) when you offer a 10 euro note. Come loaded with change when visiting a patisserie traditionnelle.
C'est comme ca!