Charred Spring Onion Pizza - The Local Palate

Ingredients

• 1 ball pizza dough
• 4 ounces béchamel (recipe follows)
• 1 quart spinach, cleaned
• 1 cup shredded mozzarella, divided
• 4 ounces cooked and diced pancetta
• ¼ cup charred spring onion
• 2 ounces aged balsamic vinegar
• 3 ounces grated Parmigiano Reggiano
• 2 tablespoons butter
• 2 tablespoons flour
• 1¼ cups whole milk, heated
• Salt and pepper