A visit to Paris is not complete without a visit to an outdoor market. You can Google which ones are the best, of course this is entirely subjective. I feel like going to the market is the only reason people in Paris get up early in the mornings, so if you plan to visit one of these markets make sure to get there before it closes (usually around 1-2pm).
We visit the market by our place at least once a week, it runs on Wednesdays and Sundays. This is my favorite market in Paris because it's close to our apartment and, most importantly, it's covered by the metro line that runs above it. It's perfect for rainy winter days like the ones we've been having.
Produce makes up a lot of the fare for sale. But there are all kinds of things you can buy here.
Poor lapin :(
I always stop at this one bakery stand. It has Polish candies and the two women that run it are both Polish/French. They usually yell at me for one reason or another. We decided to buy the olive bread because it looked so good. Except we came back to buy it, and it was gone. I think DJB cried a little.
The flowers for sale are also amazing. The only thing I wouldn't buy here are the clothes.