Preheat your grill to medium-high heat, around 375-400°F (190-200°C).
Heat olive oil in a skillet over medium heat. Add chopped onion, celery, and green bell pepper. Sauté until vegetables are softened, about 5-7 minutes. Remove from heat and let cool slightly.
In a large mixing bowl, combine the ground chuck, ground pork, breadcrumbs, Creole seasoning, black pepper, chopped parsley, eggs, and 1/4 cup of ketchup. Add the sautéed vegetables and mix until everything is well combined.
Shape the mixture into a loaf and place it on a sheet of aluminum foil sprayed with cooking spray. Shape the loaf to fit your grill's cooking area, making sure it's not too thick to cook through evenly.
In a small bowl, mix together the remaining 2 tablespoons of ketchup with the brown sugar. Spread this mixture evenly over the top of the meatloaf.
Place the meatloaf directly on the grill and close the lid. Grill for about 45-55 minutes, or until the internal temperature reaches 160°F (71°C) on an instant-read thermometer.
Once cooked, remove the meatloaf from the grill and let it rest for a few minutes before slicing.
Serve slices of the Cajun meatloaf with your favorite sides like mashed potatoes, coleslaw, or grilled vegetables. Enjoy your Cajun-inspired meal straight from the grill