Italian Sausage, Gnocchi and Tomato Soup

Bahan-bahan (6 porsi)

• 1 pound ground Italian sausage*, spicy or mild
• 1 tablespoon olive oil, divided
• 1 medium white onion, diced
• 2 large carrots, diced
• 3 stalks celery, diced
• 2 bell peppers, diced (I used one red, one yellow)
• 5 cloves garlic, peeled and minced
• 1/2 cup dry red or white wine
• 4 cups chicken stock
• 2 (15-ounce) cans tomato sauce
• 1 (15-ounce) can diced tomatoes (I used fire-roasted)
• 1 tablespoon Italian seasoning
• 1 teaspoon crushed red pepper flakes (or more to taste)
• 1 (16-ounce) package gnocchi
• 2 large handfuls fresh baby spinach or roughly-chopped kale
• optional toppings: freshly-grated Parmesan cheese, finely-chopped fresh parsley or basil