I don´t mind to spend a little more money than usual if the restaurant is great. I would like to go to a place that isn´t popular among tourists and has a warm atmosphere to have a nice meal with my boyfriend
After much thought, I am still having trouble answering this question. There are so many romantic restaurants in Paris. My first thought was that the view is what makes a restaurant romantic. If that were true, I would say it is La Tour d'Argent. The view of the river and Notre-Dame de Paris is unsurpassed, especially at dinner when you can watch the sun go down. Unfortunately, dinner there will set you back at least 180€ for dinner a lunch menu for 85€. All prices are per person and without drinks. It is a very traditional restaurant with more waiters in formal wear than any other restaurant I have seen. A tour of the beautiful wine cellar makes it even more romantic.
Another restaurant with a great view is Le Jules Verne on the second floor of the Eiffel Tower, where super-star chef Alain Ducasse presents a more up to date menu for slightly more money.
Most people are not going to want to pay 500€ for dinner or 300€ for lunch. There are other restaurants with great views, but what they all seem to have in common is that they have low quality to price ratios. Maybe a view is not that important?
One of my favorite restaurants in Paris is Dominique Bouchet.
It's an intimate, romantic, jewel-box of a restaurant with some of the best food and service in Paris. About 80€ to100€ for dinner and a 55€ lunch menu.
Another restaurant that I think of as romantic would be Le Restaurant de L'Hotel. It is about 110€ to 140€ for dinner and a pretty reasonable 35€ for two courses and 45€ for three courses on the lunch menu.
I would also put La Méditerranée into the mix.There are beautiful, playful murals inside the dining rooms and a nice enclosed terrace with lots of light during the day. The food is inspired by the South of France and the excellent fish dishes are the way to go. They have a well-priced 36€ three course menu with choices at dinner and a la carte will run 50€ to 60€.
Finally, there are the sister restaurants, Au Bon Accueil and Chez Les Anges. The former has outside tables for two with a nice view of the Eiffel Tower. Try to reserve one of them and you have a view:
Both restaurants have nice interiors, very reasonably priced three course menus (32€ and 35€ respectively) with a la carte prices higher. Excellent food and service at both. Don't get stuck in the little back room of ABA though.
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Le Taillevent Restaurant is amazing. Reservations are a MUST.
I would check out Chez Julien. It's so romantic it doesn't look real and in what I think is the most romantic part of the city. I think you can do dinner there for around 60-70 euro without drinks if not a bit less. Totally worth it, though.
You can go to Le Jardin d'en face, very good French restaurant (and not very expensive) in a romantic area near Montmarte.