Prepare the Chicken – Cut the chicken breasts in half lengthwise to create 4 total portions. Place a piece of plastic wrap on top and flatten to ½-inch thick. Repeat with the remaining pieces. Evenly season both sides with salt and black pepper. Add the chicken to a baking dish or a large resealable plastic bag.

Cook the Chicken – Heat a large skillet over medium heat, then add 2 tablespoons olive oil. Once hot and shimmering but not smoking, add the chicken. Use tongs to press down into the pan for maximum contact. Cook until golden brown, about 5 to 7 minutes. Flip and cook until the internal temperature reaches 160ºF (71ºC), about 5 minutes. Transfer to a clean plate and cover to keep warm.

Make the Sauce – Reduce the heat to medium-low and add 1 tablespoon of olive oil to the pan. Cook the garlic for 30 seconds. Add the cherry tomatoes, stir, and cook until they soften, about 4 minutes. Stir in the heavy cream, pesto, and sun-dried tomatoes. Simmer until the sauce is thickened, about 3 to 5 minutes.

Warm the Chicken – Add the chicken back to the pan with the sauce. Turn to coat and simmer until hot, about 2 minutes.

To Serve – Serve whole or slice into pieces. Drizzle the sauce on top. Garnish the creamy pesto chicken with sliced basil.