General romantic ambiance:
* Intimate
* Enchanting
* Cozy
* Charming
* Sensual
* Ethereal
* Dreamy
* Serene
* Romantic (of course!)
Focusing on the setting:
* Candlelit
* Secluded
* Private
* Elegant
* Sophisticated
Focusing on the feeling:
* Passionate
* Passion-filled
* Seductive
* Love-filled
* Tender
* Evocative
More evocative options:
* Enchanted
* Bewitching
* Mesmerizing
Ultimately, the best word depends on the specific details of the dining experience you want to describe.