French Onion Cabbage Gratin - Testing

https://www.delish.com/cooking/a63393634/french-onion-cabbage-gratin-recipe/ 

https://www.facebook.com/reel/934125715244689

1 - It was good, but the cabbage was a bit flat. What could I do to make it more succulent? Browning at a higher temp? Injecting flavor somehow?

2 - This second attempt was delicious! The changes I made paid off and, as usual, I think the real key is once again to use browning as a key element. A green salad and bread helped balance the meal.

Number of portions: 6

Serving size: ~450 g

Calories per serving: ~550 kcal

Speed: Slow Food

Experienced cook (active time): 1 hr 40 min

Novice cook (active time): 2 hr 15 min

Total elapsed time: 3 hr

LHSS Score: 7.3 / 10

1 small head of green cabbage (about 2 lb.), cut into 1" slices

2 Tbsp. bacon fat

2 Tbsps. (1oz/28gr) butter 

½ cup panko breadcrumbs

1/4 tsp Salt 

2 Tbsps. (1oz/28gr) butter 

2 large yellow onions (20oz/570g) thinly sliced into half-moons

1 tsp. salt

2 fresh thyme sprigs

1/3 cup dry white wine

Freshly ground black pepper

2 Tbsp. all-purpose flour

1½ cups heavy cream

1½ cups milk 

(OR 3 cups ½+½ cream)

1½ cups grated Gruyère (6.3oz/180g) divided

1 or 2 oz crumble Cambozola cheese

Freshly ground black pepper

1. Prep the oven and cabbage: Preheat your oven to 400°F (200°C). Line a large, rimmed baking sheet with parchment paper or lightly grease it. Place the cabbage steaks in a single layer on the pan, leaving some space between them. Brush both sides of each cabbage steak evenly with the oil and season with salt and pepper. Bake for 15 minutes, then flip and roast another 15 minutes, or until the edges are golden brown and crispy. For extra crispiness, you can broil for the last 1–2 minutes, watching closely to prevent burning. (I HAD TO COOK 20 MINUTES LONGER UNTIL CENTERS SOFT)
2. First, in a straight-sided, 12" oven-ready skillet over medium heat, melt 2 Tbsp. butter. Add the breadcrumbs and season with 1/4 tsp. salt. Cook, stirring frequently, until the breadcrumbs are golden brown, 3 to 4 minutes. Set aside and wipe the pan.
3. Melt 2 Tbsps. butter in the pan and cook the onions with the salt, stirring occasionally, until the onions are jammy and deep golden brown, 35 to 50 minutes.
4. Add the fresh thyme and the wine, scraping up the bottom of the pan as the wine loosens the fond. Simmer, stirring, until the liquid is reduced by 1/2 and the onions return to their jammy consistency, 1 to 2 minutes more; season with pepper. Set the onions aside. 
5. In the same skillet over medium heat, melt the remaining 2 Tbsps. of butter. Add the flour and cook, stirring constantly, until a bubbling blonde paste forms on the bottom of the pan. 
6. Whisk in the cream and milk. Bring to a boil then simmer, stirring occasionally, until reduced and slightly thickened, 5 to 7 minutes. 
7. Fold in 1 cup of Gruyère, the Cambozola and three-quarters of the caramelized onions.
8. Nestle the cabbage in the pan and season all over with 1 tsp. salt. Turn off the heat and let sit 10 minutes.
9. Set the rack in middle of the oven and preheat to 350°F. 
10. Spoon the sauce over the cabbage then top with the remaining caramelized onions, followed by the remaining 1/2 cup of cheese and half of the breadcrumbs.
11. Transfer to the oven and bake gratin until cabbage is tender, about 20 minutes. Top with the remaining breadcrumbs and thyme; season with pepper, cook another 20 minutes.
12. Serve with green salad and bread.