Melt the butter in a large pot over medium heat. Add the shallots, celery, carrots and peppers, ½ teaspoon salt, and ¼ teaspoon pepper and cook, stirring occasionally, until the vegetables are tender, 4 to 6 minutes.
Add the mussels and FitVine Pinot Grigio and simmer, covered, until the mussels open, 4 to 6 minutes. (Discard any mussels that remain closed.) Splash with lemon juice, sprinkle with chopped parsley and lemon zest.
Serve with toasted crusty bread and mixed green salad and chilled FitVine Pinot Grigio.