Season chuck roast with salt and pepper.
Heat oil in a large pot over medium-high heat.
Sear the roast on all sides until browned. Remove and set aside.
In the same pot, sauté onion, garlic, and ginger until fragrant.
Stir in soy sauce, honey, hoisin sauce, brown sugar, rice vinegar, sesame oil, and chili flakes.
Return roast to the pot and spoon sauce over the top.
Cover and cook on low heat for 3–4 hours (or in a slow cooker for 6–8 hours) until tender.
Remove beef and shred or slice.
Simmer sauce until thickened into a sticky glaze.
Coat beef in the glaze and serve.
Garnish with green onions and sesame seeds.
