Cook the yuca in a large pot with salted water over medium heat for about 15 minutes or until fork tender.
Adjust oven rack in the middle position and preheat to 375° F.
Drain the yuca and remove any fibers from the center. Transfer to a large bowl and mash.
Heat the heavy cream, chicken or vegetable bouillon, garlic, butter and salt in a small pot over medium heat.
Add the cream mixture, beaten egg, parsley and chives to the mashed yuca and mix well.
Transfer the yuca mixture to a greased baking dish, sprinkle with the parmesan cheese on top and bake for about 30 minutes or until golden in some parts. Serve warm.