Preheat the oven to 350°F (175°C).

In a large mixing bowl, combine softened cream cheese, sour cream, and mayonnaise. Mix until smooth and creamy.

Stir in the shredded mozzarella, cheddar, and grated Parmesan cheeses until fully incorporated.

Gently fold in diced green onions, red bell pepper, garlic powder, onion powder, Italian seasoning, salt, and pepper.

Transfer the mixture to a baking dish and spread it evenly.

Bake for 25-30 minutes until the top is golden brown and bubbly.

Let cool for about 5 minutes before serving.