Rinse the corned beef under cold water to remove excess salt. Place it in a large pot and cover it with water. Add bay leaf, thyme, parsley, and onions. Bring to a boil, then reduce to a simmer for 3-4 hours until fork-tender.

Strain the cooking liquid, discarding the herbs and onions. Add carrots and Yukon Gold potatoes. Season with kosher salt and pour reserved cooking liquid back in. Simmer for 30-40 minutes until vegetables are tender.

Bring liquid back to a boil and add the quartered cabbage. Season with salt and black pepper. Simmer uncovered for 10-15 minutes until tender but slightly crunchy.

Optionally, remove corned beef, place on a baking sheet, and broil for about 5 minutes until browned. Watch closely to prevent burning.

Slice corned beef against the grain and serve with vegetables and broth spooned over the top.