In a large pot, warm the sun-dried tomato oil over medium-high heat. Add the chopped onion and sauté for 4-5 minutes until translucent and slightly browned.

Stir in the minced garlic and chopped sun-dried tomatoes, cooking for an additional 2-3 minutes.

Add the tomato paste to the pot, mixing it in thoroughly and cooking for another 2 minutes.

Carefully pour in the chicken stock while stirring to deglaze the pot, allowing the mixture to come to a gentle simmer for about 2-3 minutes.

Once the stock has incorporated, mix in the heavy whipping cream, seasoning with salt, black pepper, and red chili flakes.

Add the penne pasta to the pot, ensuring it is fully coated in the creamy sauce. Reduce heat and cook uncovered for about 10 minutes.

Gently incorporate the fresh spinach and basil into the pasta, stirring until the spinach wilts, about 2-3 minutes.

Stir in the grated parmesan cheese until it melts into the sauce.

Scoop the One-Pot Spinach Tomato Pasta into bowls, garnishing with additional parmesan if desired.