1. Generously season beef chuck roast with salt and pepper.
2. Heat a large skillet over high heat; add vegetable oil. When oil is hot, brown roast on all sides, about 2 minutes per side. Remove pan from heat.
3. Spread chopped onions in slow cooker; place browned roast on top of onions.
4. Spoon red chili paste into the hot skillet. Add cumin and coriander. Rub mixture into hot oil with the back of a spoon to blend. Place skillet over medium heat.
5. Pour in chicken stock. Return heat to high. Stir in coconut milk. Add diced tomatoes with green chiles, fish sauce, brown sugar, minced garlic, tomato paste, and sliced ginger; stir in lime juice. Bring to a boil.
6. Pour mixture over pot roast; add bay leaves. Stir to distribute ingredients in the slow cooker.
7. Cover slow cooker and set to Low. Cook until fork tender, 7 to 8 hours.
8. Remove meat from the broth. If desired, skim some fat from the surface of the broth.
9. Place potatoes and bok choy into the broth; stir. Cover and turn heat to high. Cook until potatoes are tender, about 12 minutes.
10. Blend cornstarch and water in a small dish until dissolved. Stir into broth mixture.
11. Cut meat into large chunks and add to the slow cooker; stir. Cover slow cooker and cook on high until meat is heated through and broth is slightly thickened, about 12 minutes.
12. Ladle into serving bowls and garnish with chopped peanuts and cilantro.

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