In a large braiser, bring salted water to a boil. Add the potatoes and green beans and cook for 3 minutes. Drain. Transfer to a plate.
Preheat your oven to 375°F (190°C), and while it warms up, mix together 1/2 cup Dijon mustard, 1/2 cup honey and 2 tablespoons lemon juice. Keep aside.
Season the chicken breast all over with garlic powder, salt, paprika and pepper. In the same braiser heat olive oil over medium high heat and sear the chicken until golden brown, about 3 minutes each side. Add the onion and garlic and cook until garlic is fragrant, about 1 minute.
Next, return the potatoes and green beans into the braiser and pour the honey mustard sauce over the chicken and vegetables.
Bake for twenty minutes in the preheated oven or until the chicken is cooked through and vegetables are tender.
Garnish with oregano or parsley leaves.
Serve immediately and enjoy!