1 3/4lb boneless skinless chicken breast cup into 1" pieces
1/2 tsp dried oregano
2 tbsp all purpose flour
1 1/2 cups low sodium beef broth
1 cup shredded Gruyère
Freshly chopped parsley
Directions
In a large skillet over medium heat, heat 2 Tbsp. oil. Add onion and thyme; season with salt and pepper. Reduce heat to medium-low and cook, stirring occasionally, until onions are caramelized and jammy, about 25 minutes. Stir in garlic and cook, stirring, until fragrant, about 1 minute more. Transfer onion mixture to a plate. Wipe skillet clean.
In a large bowl, sprinkle chicken with oregano; season with salt and pepper, then toss with flour. In same skillet over medium-high heat, heat remaining 1 Tbsp. oil. Cook chicken, stirring occasionally, until golden brown on all sides and mostly cooked through, about 8 minutes.
Add broth and return onions to skillet. Bring mixture to a boil, then reduce heat to medium-low and simmer until liquid slightly reduces and an instant-read thermometer inserted into thickest part registers 165°, about 10 minutes more.
Add Gruyère and cover skillet with a lid. Cook, undisturbed, until cheese is melty, about 2 minutes. Top with parsley.