In a medium saucepan over medium heat, cook the lentils in salted simmering water until tender, about 25 minutes, adding the chopped haricots verts during the last minute of cooking, drain and let cool.
In a large bowl whisk the white wine vinegar, minced shallot, Dijon mustard, and chopped thyme, whisk in the olive oil. Add the lentils, haricots verts, sliced radishes, torn frisée, and cup pitted olives.