Trim the ends off fresh green beans and set aside. Mince garlic cloves and fresh ginger finely. Pat chicken thighs dry and season lightly with salt and pepper.
In a small bowl, whisk together soy sauce, honey, minced ginger, and garlic until honey dissolves. Set aside the teriyaki sauce.
Heat olive oil in a skillet over medium-high heat. Add chicken thighs in a single layer and cook 4-5 minutes per side until golden and cooked through. Remove chicken and set aside.
Add sesame oil to the same skillet and sauté green beans for 3-4 minutes until tender-crisp and bright green.
Return chicken to skillet with green beans. Pour teriyaki sauce over everything. Mix cornstarch with water until smooth and pour into skillet. Stir gently to coat chicken and beans evenly.
Lower heat to medium and simmer for 2-3 minutes until sauce thickens and becomes glossy.
Sprinkle sesame seeds and chopped green onions on top. Serve immediately with steamed rice or noodles.
