Mashed Potatoes with Hearty Vegetable Gravy

Ingredients

• 1 cup Greek Yogurt
• 1/2 teaspoon salt
• 2 Tablespoons butter
• 1/4 teaspoon pepper
• 1 cup frozen peas
• 1 red bell pepper (chopped)
• 1 cup carrots (chopped)
• 8-10 Russet potatoes
• 1/2  cup  onion  (minced)
• 4 Tablespoons  butter
• 2/3  cup  flour
• 2 1/2 cups  2% milk 
• 1 Tablespoon Better than Bouillon” chicken base
• 1  teaspoon  salt
• 1/2  teaspoon  pepper
• 1-2 small zucchini squash (chopped)
• 1/2 cup rotisserie chicken (shredded)