Kale Au Gratin

Ingredients (were originally doubled):

onion

2-3 garlic cloves

1 cup heavy cream

1 rosemary sprig

3/4 tsp. Diamond Crystal or 3/8 tsp. Morton kosher salt, plus seasoning to taste

1/4 tsp. freshly ground black pepper, plus seasoning to taste

2 large bunches of Tuscan kale and/or Swiss chard (1–1 1/4 lb. total)

1/2 lemon

1/8 tsp. crushed red pepper flakes

3 oz. high-quality sharp cheddar cheese

1/4 cup breadcrumbs (panko or I like Schar GF)

1 tsp. extra-virgin olive oil

Preparation

Step 1 (Cream sauce): 

In a large pot, add a few T diced onion (or more if you like), 2-3 cloves of minced garlic, heavy cream, rosemary sprig, salt and black pepper. Bring to a simmer over low heat and cook, stirring occasionally, until onion and garlic are very soft, 15–20 minutes.

2. While cream cooks, remove ribs from 4 medium bunches of (Tuscan) kale (I actually like cutting up the ribs and including them with my thousand head kale). Tear leaves into big pieces and wash. It’s okay if some water still clings to the leaves—this will help them wilt later. If you don’t have a bowl big enough to hold all of your greens, pile them on a baking sheet instead.

3. When cream is ready, pluck out rosemary sprig and discard. Finely grate zest of ½ lemon into cream and stir in ¼ tsp. crushed red pepper flakes. 

4. Either heat a large (as large as possible—12" is the goal) ovenproof skillet over medium OR just add the Kale to the cream sauce and transfer to a small baking dish (7x11 is what I used). Add some of the greens, cover skillet (use a baking sheet if you don’t have a lid), and cook until wilted, 3–4 minutes. Scoot wilted greens to one side of pan. Keep adding until all in the pan, covering pan, and cook to wilt, 3–4 minutes. Add lemon juice and cream sauce if you cooked the kale separately from the sauce. Remove from heat and place skillet on a rimmed baking sheet or transfer to oven safe pan.

5. Cut sharp cheddar cheese into ¼"-thick slices (or just used shredded). Combine bread crumbs, extra-virgin olive oil, season with salt and pepper, and add on top of kale. Bake at 350 until cheese is browned and bubbling and panko is toasted, 50–55 minutes.