Preheat the oven to 400 degrees F. Then set a large oven-safe skillet over medium heat.
Add the butter, chopped bell pepper, chopped onion, and garlic in the skillet. Sauté for 3-5 minutes to soften.
If using “popcorn” shrimp there is no need to chop it. However, if you are using larger shrimp, roughly chop into small ½ inch pieces. (Small enough to scoop up on crackers.)
Once the vegetables are softened, add the shrimp and Cajun seasoning. Sauté for 1-2 minutes.
Stir in the cream cheese, mayonnaise, cheddar cheese, ¼ cup parmesan cheese, scallions, lemon juice, and hot sauce. Stir until the cream cheese, and shredded cheese melts into a thick sauce. Turn off the heat.
Sprinkle the top with the remaining ¼ cup parmesan cheese. Bake for 12-15 minutes, until the edges are bubbly. Serve warm with crackers, tortilla chips, potato chips, or cut vegetables.
Don't Have An Oven-Safe Skillet? Prepare the dip on the stovetop using any skillet. Then transfer it to a 9 X 9 inch baking dish before placing in the oven.