Cook the chicken:

Melt the butter in a large soup pot or Dutch oven over medium-high heat. Once it’s hot, add the diced chicken along with the dried basil, oregano, garlic salt, and a pinch of pepper. Sauté for about 4–5 minutes, stirring occasionally, until the chicken is golden on the outside and mostly cooked through.

Sauté the veggies:

Add in the diced onions and sundried tomatoes, followed by the minced garlic. Cook everything together for 3–4 minutes until the onions become soft and fragrant.

Make a roux:

Sprinkle the flour over the mixture in small amounts, stirring well after each addition to coat everything evenly and prevent clumping. Stir in the tomato paste and let it cook for another minute to deepen the flavor.

Add the broth:

Slowly pour in the chicken stock, stirring constantly to avoid lumps and to lift up any browned bits from the bottom of the pot. Bring everything to a gentle boil.

Simmer and season:

Once the soup is bubbling, reduce the heat to low and let it simmer uncovered for about 15–20 minutes, or until the chicken is fully cooked and the broth has thickened slightly.

Creamy finish:

Stir in the softened cream cheese until fully melted, then add the shredded mozzarella and mix until smooth and velvety.

Add greens:

Toss in the fresh spinach and let it wilt for a couple of minutes. Give the soup a taste and adjust salt and pepper if needed.