In a large saucepan, cover the lentils with 2 inches of water and bring to a boil. Season with salt and simmer over moderate heat until tender, 40 minutes. Drain the lentils.

Heat the olive oil in a large, deep skillet. Add the red onion and cook over moderate heat, stirring occasionally, until softened, about 5 minutes. Add the garlic and cook until fragrant, about 1 minute. Add the lentils and the wine and simmer until the wine has been absorbed, about 5 minutes. Add the spinach and stock and cook, stirring occasionally, until the spinach is wilted, about 5 minutes. Stir in the creme fraiche. Add the mache, parsley and cilantro and cook until barely wilted, about 2 minutes. Season with salt and pepper and serve warm.