Preheat the oven to 350°F (175°C).
In a large mixing bowl, combine the cream cheese, sour cream, and mayonnaise until smooth.
Add the shredded cheddar cheese, chopped broccoli, minced garlic, salt, black pepper, and red pepper flakes to the bowl.
Transfer the mixture into a greased baking dish.
Bake in the preheated oven for 25-30 minutes, or until the dip is hot and bubbling.
Once baked, remove the dip from the oven and let it cool for a few minutes before serving.
Serve with toasted bread, tortilla chips, or fresh vegetables for dipping.