1. Cut the onions into eighths lengthwise.
Clean the button mushrooms with a paper towel, then slice them.
Zest the lemon using a fine grater and squeeze the juice.
Finely chop the chervil and roughly chop the tarragon.
2. Heat the olive oil over medium heat in a large skillet and cook the onions for 10 to 12 minutes until they soften.
3. Add the mushrooms and sauté for another 5 to 7 minutes.
4. Season with salt and pepper.
5. Meanwhile, heat a medium-high saucepan and dry-toast the pearl couscous for 1 minute.
Add the broth and simmer for 12 minutes.
6. Drain, fluff with a fork, and set aside uncovered.
7. Meanwhile, in a small bowl, mix together the ricotta, grated pecorino, ¼ tsp of lemon zest, and ½ tbsp of lemon juice per person.
Season with salt and add a generous amount of black pepper.
8. In the skillet with the onions and mushrooms, add the butter, half of the chervil, half of the lemon ricotta mixture, and the pearl couscous, then mix well.
9. Serve the couscous on plates and garnish with the remaining lemon ricotta mixture.
Sprinkle with the remaining chervil, tarragon, and lemon zest to your liking.
Drizzle with the remaining lemon juice if desired.