Coat the boneless skinless chicken breasts thoroughly with Cajun seasoning, salt, and black pepper, ensuring even coverage. Set aside.

In a large skillet, heat a tablespoon of avocado oil over medium-high heat. Add shaved Brussels sprouts and shallots. Sauté for 3-5 minutes until tender.

Lower the heat and add additional avocado oil if needed. Cook seasoned chicken breasts for 3-4 minutes per side until golden and cooked through. Let rest and cube.

In a medium bowl, whisk together Greek yogurt, Parmesan cheese, lemon juice, minced garlic, Dijon mustard, and Worcestershire sauce until smooth.

In a large bowl, combine sautéed Brussels sprouts and shallots with the dressing. Add cubed chicken and crunchy quinoa, mixing until well incorporated.

Transfer to serving plates, garnish with additional Parmesan or quinoa, and serve warm with gluten-free bread.