Preheat your oven to 400 degrees F. Move an oven rack to one slot below the center.* Grease a baking sheet with non-stick cooking spray. Set aside.
Cut 1 large head green cabbage into 4 large slices** and arrange them in a single layer on the prepared baking sheet.
In a small saucepan, add the 6 tablespoons unsalted butter and 3 cloves garlic and place over low heat. Cook until the butter is melted, 2-3 minutes.
Brush the garlic butter over both sides of the cabbage steaks and then sprinkle with salt & pepper.
Bake for 25-30 minutes, rotating the baking sheet halfway through, until the edges are browned and crisp and the centers are tender.
Remove from the oven and garnish with chopped fresh parsley and Parmesan cheese if desired. Serve warm.
Notes
*Moving the oven rack to the position just below the middle will help prevent over-browning on top. **For the best texture, cut the cabbage into even ¾-inch-thick slices. Start by cutting the cabbage in half, then cut slices from the center outward to maximize surface area for each steak.