Start by trimming the chicken breasts and cutting them into 2-inch pieces. Season lightly with salt and pepper. Set aside.
Heat a tablespoon of olive oil in a skillet over medium heat. Add the minced garlic and cook until fragrant, about 30 seconds, until you smell a warm, inviting aroma.
Transfer the garlic to the bottom of your slow cooker. Layer the seasoned chicken pieces over the garlic and pour in the chicken broth.
Top the chicken with the chopped spinach, spreading it evenly so it wilts into the sauce as it cooks. Dollop the softened cream cheese over everything for richness.
Cover the slow cooker and cook on low for 4 hours, or on high for about 2 hours, until the chicken is tender and the spinach is fully wilted.
About 10 minutes before serving, open the lid and sprinkle the grated Parmesan cheese over the dish. Cover again and let it melt into the sauce, creating a silky, cheesy finish.
Once the cheese has melted, check the dish for seasoning. Taste the sauce and add a pinch of salt or a squeeze of lemon juice if desired to brighten the flavors. Serve hot, spooning the creamy greens and chicken onto plates.
