Peel the garlic and red onion, chop the onion into chunks. In a food processor, blend the chopped onion, dry lemongrass, red chili, and ginger puree until smooth, about 1-2 minutes.

Heat vegetable oil in a large skillet over medium-high heat. Brown the stewing beef in batches, seasoning with salt and pepper for 4-5 minutes on all sides.

Remove the beef and lower heat to medium. Add onion paste to the pan and sauté for 2-3 minutes until it begins to caramelize.

Return browned beef to the skillet, stir in coconut milk and tomato paste, followed by the spices. Mix for 2 minutes before transferring to a slow cooker.

In the slow cooker, combine beef mixture with bay leaves and chilies. Cook on high for 4 hours or low for 8 hours.

Once cooked, check seasoning and adjust if necessary. Serve garnished with fresh coriander alongside rice.