Preheat the oven to 350°F (175°C). Lightly grease a 9-inch baking dish.
In a large mixing bowl, combine the thawed and drained spinach, softened cream cheese, sour cream, mayonnaise, Parmesan cheese, garlic powder, onion powder, salt, and pepper. Mix until smooth and well combined.
Transfer the mixture to the prepared baking dish and spread it evenly.
Bake in the preheated oven for 25–30 minutes, or until the dip is hot and bubbly and the top is lightly golden.
Let cool slightly before serving warm with tortilla chips, bread, or vegetable sticks.
Notes
Serve warm with your favorite dippers for an easy appetizer or party snack.