We used a combination of 'French Breakfast,' 'White Icicle,' and 'Pink Beauty' radishes, but you can use any variety you'd like.
Make the dip: Stir ricotta, parsley, dill, and basil in a medium bowl. Season with salt and pepper.
Serve radishes with bowls of dip, butter, and fleur de sel.
Dip can be refrigerated in an airtight container up to 2 days. When the weather is hot, sprinkle radishes with crushed ice before serving to keep them crisp.