Kale Pasta

Name: Kale Pasta
Prep time: 10 min
Cook time: 20 min
Total time: 30 min
Cuisine: Italian
Ingredients: 1/2 cup walnut halves (roughly chopped); 8 ounces whole wheat spaghetti (or other long pasta); 1 1/2 tablespoons extra virgin olive oil (plus additional for tossing with the pasta); 2 large red onions (thinly sliced); 2-3 large bunches kale (about 2 pounds, stems removed and chopped); 4 cloves garlic (minced); 1 can diced tomatoes in their juices ((14 ounces)); 2/3 cup dry white wine (such as Pinot Grigio); 1/2 teaspoon crushed red pepper flakes (reduce to 1/4 teaspoon if sensitive to spice); 1/4 teaspoon kosher salt (plus additional to taste); 1/8 teaspoon ground black pepper; 1/2 cup freshly grated Parmesan cheese