Creamy Tomato Tortellini Soup (Cozy 35-Minute Dinner)

Ingredients

• 1 tablespoon olive oil
• 1 medium yellow onion, finely diced
• 3 garlic cloves, minced
• 2 tablespoons tomato paste
• 1 teaspoon Italian seasoning
• 1/4 teaspoon red pepper flakes, optional
• 1 (28 oz or 795 g) can crushed tomatoes
• 4 cups (950 ml) low-sodium vegetable broth
• 1/2 teaspoon kosher salt, plus more to taste
• 1/4 teaspoon black pepper
• 18 oz (510 g) refrigerated cheese tortellini
• 3/4 cup (180 ml) heavy cream
• 1/2 cup (50 g) freshly grated Parmesan cheese, plus more for serving
• 3 cups (85 g) baby spinach
• 1/4 cup fresh basil leaves, torn