Bring a large pot of salted water to a rolling boil over high heat. Add penne pasta and cook according to package directions, about 10-12 minutes, until al dente. Drain pasta and set aside, reserving a little pasta water if needed.

In a large skillet, heat a tablespoon of olive oil over medium-high heat. Season chicken breasts with salt and pepper. Sauté chicken for about 6-7 minutes on each side until golden brown and cooked through. Remove and slice into strips.

In the same skillet, lower heat slightly and add minced garlic. Sauté garlic for 1-2 minutes until fragrant. Pour in heavy cream, stirring well. Allow to simmer for about 3-4 minutes until it thickens slightly.

Add fresh spinach to the sauce, stir in and cook for 2-3 minutes until wilted.

Return the sliced chicken and drained penne to the skillet. Toss everything over low heat, adding reserved pasta water if needed to reach desired consistency.

Serve warm, optionally garnished with extra Parmesan cheese and fresh spinach leaves.