Gail Simmons’ Epic Spaghetti Pie

Spaghetti pie is a big affair, impressive in both stature and ingredients — perfect for a hungry crowd. INGREDIENTS: Unsalted butter, for greasing the pan 2 tablespoons extra-virgin olive oil 1 medium yellow onion, finely chopped 2 cloves garlic, finely chopped ¾ lb broccoli or broccoli rabe, trimmed, stems and florets chopped into ¼-inch pieces (about 2 ½ cups) 1 lb hot or sweet Italian sausage, removed from casings 1 tablespoon tomato paste 1 (28-ounce) can whole peeled tomatoes, drained, tomatoes crushed by hand Kosher salt 1 lb dried spaghetti ¾ cup whole milk (I substituted half & half) 3 large eggs 2 teaspoons freshly ground black pepper 2½ cups (8 oz) grated sharp cheddar cheese 2½ cups (8 oz) grated fontina cheese 1½ cups (3 oz) freshly grated Parmigiano-Reggiano cheese, divided 1 tablespoon finely chopped fresh sage