Melt 2 tablespoons of butter in a large skillet over medium heat. Add 3 sliced yellow onions and a pinch of salt. Sauté for about 20 minutes until golden brown and caramelized.

Lower the heat and pour in 2 tablespoons of balsamic vinegar and 1 tablespoon of Worcestershire sauce. Add 1 teaspoon of dried thyme and stir well. Cook for another 2-3 minutes until fragrant.

In a shallow bowl, mix ½ cup of gluten-free all-purpose flour with salt and pepper. Dredge 4 chicken breasts in the flour mixture. Cook in the skillet for about 5-7 minutes on each side until golden brown and cooked through.

Remove chicken and deglaze the pan with 1 cup of chicken broth and 2 tablespoons of Dijon mustard. Scrape up any bits, simmer for 5 minutes to reduce.

Return chicken to skillet and spoon sauce over. Top with caramelized onions and 1 cup of shredded Gruyere cheese. Cover and cook on low for 3-5 minutes until cheese melts.

Cook 1 cup of wild rice according to package instructions. Serve rice in bowls, top with cheesy chicken and add peas and parsley for garnish.