New Tuna Casserole | Lazy Cooking

Ingredients

• ***For the casserole:***
• 1 (8-ounce) package thin green beans or haricots verts, cut into 1-inch pieces
• 6 tablespoons butter, divided
• 2 medium leeks, thinly sliced
• 2 (4-ounce) packages fresh gourmet mushroom blend
• 1/4 cup all-purpose flour
• 3 cups heavy cream
• 1 cup organic vegetable broth
• 2 cups sharp white cheddar cheese, shredded
• 6 tablespoons parmesan cheese, grated, divided
• 3/4 teaspoon kosher salt
• 1/2 teaspoon freshly ground black pepper
• 1 (16-ounce) box ziti pasta, cooked
• 1 (12-ounce) can solid white tuna in spring water, drained
• 2 tablespoons fresh chives, chopped, plus more, to taste, for garnish
• 1 tablespoon fresh tarragon or parsley, chopped
• ***For the topping:***
• 1/4 cup potato chips, crushed
• 1/4 cup panko
• 2 tablespoons butter, melted