Preheat the oven to 325°F and adjust a rack to the center.
Prepare the cabbage. If the cabbage is without any bruising, wash and dry it. If the couple of outermost leaves are bruised or wilted, remove them, then rinse and dry. On a clean dry surface, cut off the part of the root end, just enough to clean it up, but not so much that the cabbage won’t stay intact. Cut it in half, and then cut each half into 4 even wedges. Set aside.
Make tomato base. In a small bowl, combine 2 tablespoons of the olive oil, ½ teaspoon salt, tomato paste, garlic, thyme, lemon zest and paprika. Mix to blend and set aside.
Sear the cabbage. Over high heat, add the remaining ¼ cup of olive oil to a 12 to 14-inch oven safe skillet and sprinkle it evenly with salt, about ½ teaspoon. Once it’s very hot, add the cabbage wedges. You should hear a sizzling sound when they hit the oil — if you don’t, wait until you do, otherwise you won’t get the beautiful brown caramelization. Sear for about 3 minutes on each side. (Depending on the size of the of your skillet, you might need to do this in 2 batches.) Remove them from the pan and set them aside on a plate.
Add tomato base, onions, carrots and lentils. Turn the heat to medium-high and add the tomato mixture. Use a spatula to move it around the pan. Once it begins to brown and stick to the bottom, add the onions. Cook just until they begin to soften, about 5 minutes, and then mix in the carrots and lentils.
Add the cabbage, remaining ingredients and braise. Move the onion mixture to the sides of the pan and return the seared cabbage wedges. Then move the onion mixture between and around them. Pour the stock evenly over everything, cover and place in the preheated 325°F oven for 1 hour. Remove from the oven and pour in the wine evenly over everything. Spoon some of the liquid over the cabbage and be sure all or most of the carrots and lentils are in the liquid. Add butter to the pan evenly in small pieces. Cover and return to the oven for 1 more hour. Season and serve. Season generously to taste with salt and pepper. (Here's how.)