Prep the cabbageCut the cabbage into 6 wedges, keeping the core intact so each wedge stays together. Season with salt and pepper.
Sear the wedgesHeat olive oil in a large skillet over medium-high heat. Add the cabbage wedges, cut side down, and sear until golden brown, about 3–4 minutes per side. Remove from the skillet and set aside.
Cook pancetta and onionsIn the same skillet, add the pancetta. Cook until crisp, then add the sliced onions. Sauté until the onions are soft and caramelized, about 8–10 minutes.
Deglaze with winePour in the ½ cup white wine and scrape up any browned bits from the bottom of the skillet. Let the wine simmer for 1–2 minutes to reduce slightly.
Make the cream sauceAdd the heavy cream, Parmesan, and Dijon. Stir until the sauce is smooth and gently bubbling.
Return the cabbageNestle the seared cabbage wedges back into the pan. Spoon some sauce over the top.
BraiseReduce the heat to low, cover, and cook for 15–18 minutes, or until the cabbage is tender but still holds its shape.
ServeSpoon extra sauce over the cabbage and top with fresh herbs if desired.