1. Heat a few tablespoons of olive oil in a large skillet over medium heat, then add the shallot and garlic. Cook until the shallot is soft and translucent and the garlic is fragrant, about 5 minutes. Add the spinach and cook until wilted down, about 5 minutes more.

2. In a blender, add the shallot-spinach mixture, the tarragon, basil, chives, heavy cream and ½ cup olive oil. Blend until very smooth and creamy, scraping down the side of the blender as needed. Season to taste with salt.

3. Cook the pasta according to the package directions, reserving about ½ cup of the pasta water before draining. Drain the pasta, then return it to the pot. Stir in the sauce, adding pasta water as needed to coat the pasta. Serve with a dollop of ricotta cheese.