In a large pot, combine the chicken broth, coconut milk, red curry paste, fish sauce, and lime juice. Stir well to mix the ingredients.
Bring the mixture to a simmer over medium heat.
Add the sliced chicken breasts to the pot and cook for about 5-7 minutes, or until the chicken is cooked through.
Stir in the mushrooms, bell peppers, ginger, and garlic. Cook for an additional 3-4 minutes until the vegetables are tender.
Add the baby spinach and cook for another minute until wilted.
Season with salt and pepper to taste.
Serve hot, garnished with chopped green onions and cilantro.