Preheat the oven to 400.
In a medium sized bowl, mix together the cream cheese, green onion, red pepper, garlic powder, and Parmesan until well combined.
In a microwave-safe bowl, heat the spinach in the microwave for approximately 2 minutes. Squeeze out excess water and add to the spinach to the cream cheese mixture. Stir until well combined.
Transfer the dip to an oven-safe dish and top with shredded cheddar cheese.
Bake for 15-18 minutes and let cool for 5 minutes before serving.