Chopped fresh flat-leaf parsley, for garnish (optional)
Directions
Preheat oven to 375F. Slice the cabbage in half through the stem end, then cut each half into 4 wedges, keeping the core intact so the wedges hold together.
Heat 1 tbsp oil in a large cast-iron or other heavy ovenproof skillet over high heat. Add 4 cabbage wedges and cook about 6 minutes until browned; flip and brown the other side. Transfer to a plate and season both sides with 1/8 tsp each salt and pepper. Repeat with another 1 tbsp oil and the remaining wedges, seasoning the same way.
Reduce heat to medium and add 2 tbsp oil, the butter, diced onion and garlic to the same pan. Cook, stirring constantly, until the onions are translucent, about 5 minutes. Stir in the Boursin (or cream cheese) until melted, then add the broth and the remaining 1/4 tsp each salt and pepper. Simmer a few minutes, remove from heat and stir in 1/2 cup of the Parmesan.
Nestle the cabbage wedges back into the pan. Bake 25-30 minutes until the cabbage is fork-tender. Top with the remaining Parmesan, garnish with parsley, and serve.