Kale Pasta

Bahan-bahan (4 porsi)

• 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