Trim any large fat pieces from the beef and cut into chunks. Season the beef lightly with salt and pepper.
Place beef, chopped onion, minced garlic, grated ginger, and sliced bell pepper into the slow cooker.
Pour in the coconut milk and add the curry powder and soy sauce. Stir well so the beef and vegetables are evenly coated.
Cooking
Cover and cook on low for 6–8 hours or on high for 3–4 hours, until the beef is tender and the flavors have melded.
Taste and adjust seasoning with salt, pepper, or an extra splash of soy sauce. Spoon into bowls and garnish with fresh cilantro.
Notes
Serve the curry over steamed jasmine or basmati rice, warm garlic naan, or cauliflower rice for a lighter meal. Refrigerate for up to 4 days or freeze for up to 3 months.