In a large skillet, heat 2 tablespoons of olive oil over medium heat. Swirl the oil to coat the bottom of the skillet, which should take about 1-2 minutes.

Add 1 pound of ground chicken to the skillet, breaking it into small crumbles. Sauté for 5-7 minutes until browned and fully cooked through.

Stir in 1 small finely chopped onion and 2 minced garlic cloves. Cook for an additional 2-3 minutes until the onion becomes translucent.

Pour in 1 cup of heavy cream and bring to a gentle simmer, reducing the heat slightly if needed.

Stir in 1/2 cup of grated Parmesan cheese, 1/2 teaspoon of salt, and 1/4 teaspoon of black pepper. Cook for about 3 minutes until the cheese melts completely.

Lower the heat and add in 1 cup of shredded mozzarella cheese. Stir gently until the cheese melts into the sauce.

Fold in 1/2 cup of chopped fresh spinach and cook for about 1 minute until wilted.

If desired, toast the buns until golden brown, about 2-3 minutes.

Spoon the creamy Chicken Alfredo filling onto the bottom half of each toasted bun.

Cap each assembled sandwich with the top half of the bun, pressing gently to secure.