For less than €15 per person, you can have a sumptuous feast fit for a King Louis in Paris with a view of the Eiffel Tower, Notre Dame, the Seine, or whatever classic postcard backdrop you prefer.
You just need to pick a perfect bench and put together a perfect picnic: crusty baguettes, sinfully delicious cheeses and pâtés, cured meats, fresh fruits, a bottle of wine, a bottle of mineral water, some pain au chocolat pastries for dessert.
Some of my most memorable meals in Paris have been picnics on a tiny place or back in my hotel room.
You can visit a supermarket or gourmet store for your picnic supplies, but it's more fun and Parisian to shop at the little local food stores and street markets (ask your hotel about the nearest one of those—my favorite picnic shopping is the string of little shops along the north side of rue de Rivoli, across from St-Paul church in the Marais).
Pick up a baguette at the boulangerie (bakery), cured meats and the like at a charcuterie, and other groceries at an épicerie.
Top it all off with some fruit, pastries from a pâtisserie (the French excel at these), a bottle of wine, and you're set.
The best thing about food shopping in Paris? French pastries.
Just be careful when you're buying pâté in a Paris grocery store. You wouldn't want to end up with pâtée pour chiens by accident.