Formal/Polite:
* Bonjour mon amour, comment allez-vous ? (This is the most formal and polite option, suitable for a formal relationship or someone you're not very close to.)
Informal/Affectionate:
* Salut mon amour, comment vas-tu ? (This is a more informal and affectionate way to say it, suitable for a close friend or romantic partner.)
* Coucou mon amour, comment ça va ? (This is a very casual and affectionate way to say it, suitable for someone you're very close to.)
Other Options:
* Salut mon chéri(e), comment vas-tu ? (This is a very affectionate way to say it, suitable for a romantic partner.)
* Mon amour, comment vas-tu aujourd'hui ? (This is a romantic way to say it, implying you are thinking of them specifically today.)
Note:
* "Mon amour" means "my love" and can be used for both romantic partners and close friends.
* "Chéri(e)" is more specifically used for romantic partners.
Ultimately, the best way to say it depends on your relationship with the person you're talking to.