Heat the oven to 425°F.

Heat a large Dutch oven over medium-high heat for 3 minutes. Add the oil. When it's shimmering hot, place the cabbage wedges in the pot. Cut side down. (If your Dutch oven isn't large enough, you can do this in two batches.) Roast the wedges 8 to 10 minutes, until they have a deeply golden sear all over the bottom side. If you're in no rush, do this again on the second cut side. Using tongs to transfer the cabbage wedges to a plate. Set aside.

Lower the heat to medium. Add the butter, shallots, and 2 teaspoons of the salt. Sauté the shallots, stirring occasionally, until they have started to become translucent and jammy with the occasional caramel-colored frizzle, about 10 minutes. Add the chile flakes, garlic, and ginger planks. Stir well in the center and add the tomato paste. Fry the paste in the melted butter for 2 to 3 minutes, until it turns dark red, then combine into the rest of the ingredients. Deglaze the pan with 2 cups water and the lemon juice. Stir with a wooden spoon to scrape up any browned bits freed by the liquid.

Nestle the cabbage wedges in the tomato paste mixture, caramelized sides up. Place the lid most of the way on, with a little gap, and transfer to the oven. Roast for about 40 minutes, until the cabbage has lost most of its structure and is very tender, then remove the lid and baste the wedges with the reduced sauce. Roast, uncovered, for another 5 to 10 minutes, until the sauce looks like they're extremely spent after a taxing workweek. Fish out the ginger planks and toss.

Serve the cabbage wedges with the thickened pan sauce, sprinkled with the remaining 1 teaspoon salt.