Begin by pounding the chicken breasts to an even thickness, about ½ in thick. Place the chicken breasts in a plastic bag, and use a rolling pin to pound the breasts into an even thickness. Season with pepper, and dredge each piece in flour, shaking off any excess. Set aside.

Heat ½ tablespoon olive oil in a large skillet over medium high heat. Add the chicken and cook for 5-6 minutes per side or until the chicken is cooked through and has a golden brown crust. Remove the chicken from the skillet and set aside.

In the same skillet, add the remaining ½ tablespoon of olive oil. Add the diced onion and saute for 3 minutes, then add the minced garlic and saute for another 1 minute.

Stir in the tomato paste and cook for another 2-3 minutes.

Add the chopped sundried tomatoes and the baby spinach to the skillet. Cook until the spinach wilts, about 4-5 minutes.

Reduce the heat to low. Add the cornstarch to the half and half and stir to combine. Add the cornstarch mixture, cream cheese, chicken broth and oregano to the skillet. Stir until the cream cheese is fully melted and the sauce is well combined, about 4-5 minutes.

Add the cooked chicken back to the skillet and simmer in the sauce for 4-5 minutes until the chicken is heated through.

Serve chicken with sauce.