Heat the olive oil in a large skillet or pan over medium heat. Add the chopped onion and bell pepper. Cook until softened, about 5 to 7 minutes.
Add the minced garlic to the skillet and cook for 1 minute until fragrant.
Add the ground chicken to the skillet. Break the chicken apart with a spoon and cook until it is browned throughout. Drain off any excess liquid or fat.
Stir in the Cajun seasoning, smoked paprika, oregano, thyme, and cayenne pepper. Cook for 1 minute, stirring constantly to toast the spices.
Pour in the Worcestershire sauce, chicken broth, ketchup, brown sugar, and Dijon mustard. Stir well to combine all ingredients.
Bring the mixture to a simmer. Reduce the heat to low and let it cook uncovered for 10 to 15 minutes, stirring occasionally, until the sauce has thickened to a sloppy consistency.
Taste the mixture and add salt and pepper as needed. If you prefer it spicier, add more cayenne pepper.
Lightly toast your hamburger buns. Spoon a generous amount of the Cajun chicken mixture onto the bottom half of each bun.
Top with your desired toppings, such as pickles or cheese, and place the top bun on. Serve immediately for a flavorful ground meat alternative sandwich.
Notes
For a milder flavor, reduce the cayenne pepper to 1/8 teaspoon.
If you do not have ground chicken, you can substitute ground turkey or ground pork.
This mixture freezes well. Cool completely before storing in an airtight container for up to 3 months.
Serve these Louisiana style sandwiches with coleslaw or sweet potato fries for a complete meal.