Rigatoni with Swiss Chard

INGREDIENTS

• Coarse salt and freshly ground pepper
• 1 pound rigatoni, or other tubular pasta
• 2 tablespoons unsalted butter
• 3 tablespoons extra-virgin olive oil
• 2 garlic cloves, thinly sliced
• 2 medium shallots, finely chopped
• 1 1/2 pounds Swiss chard, leaves cut into 1/2-inch strips and stems cut into 1/2-inch pieces
• 2 tablespoons finely grated lemon zest (about 2 lemons)
• 1/2 cup dry white wine
• 1/2 teaspoon red pepper flakes
• 1/3 cup fresh ricotta cheese
• 1/3 cup (about 1 1/2 ounces) pine nuts, toasted
• Freshly grated Parmesan cheese, for sprinkling