Kale Gratin Recipe

Prepare kale

Wash kale thoroughly. Strip leaves from stems and chop leaves into roughly 1-inch pieces. Blanch in a pot of boiling salted water for 1 minute until bright green, then immediately transfer to an ice bath to stop cooking. Drain well and squeeze out excess water; roughly chop again if needed. You should have about 6 cups packed.

Prep artichokes

If using canned/jarred artichokes, drain well and pat dry. Quarter each heart into bite-sized pieces. If using fresh, trim and cook until tender, then quarter. Set aside.

Roast romaine

Preheat oven to 425°F (220°C). Halve romaine hearts lengthwise. Brush cut sides lightly with 1 tablespoon olive oil and season with a pinch of salt and pepper. Place cut-side down on a rimmed baking sheet and roast for 6–8 minutes until charred at the edges but still holding shape. Remove and let cool slightly, then roughly chop into 1–2 inch pieces.

Make béchamel-style sauce

Reduce oven temperature to 375°F (190°C). In a medium saucepan over medium heat, melt butter. Add minced garlic and cook 30–45 seconds until fragrant. Stir in flour and cook for 1–2 minutes to remove raw flavor, stirring continuously until mixture is pale and bubbling.

Gradually whisk in milk and cream, continuing to whisk to avoid lumps. Bring to a gentle simmer and cook until sauce thickens to coat the back of a spoon, about 4–6 minutes. Remove from heat and whisk in Dijon mustard, 3/4 cup grated gruyère, 1/3 cup parmesan, salt, black pepper, and red pepper flakes if using. Allow the sauce to cool 2 minutes, then whisk in the beaten egg quickly to incorporate (temper the egg by whisking a small spoonful of hot sauce into the egg first if concerned).

Combine the drained chopped kale, quartered artichoke hearts, and chopped roasted romaine in a large bowl. Add lemon juice and remaining 1 tablespoon olive oil; toss to combine. Adjust seasoning with a little more salt and pepper if needed.

Pour the warm cheese sauce over the vegetable mixture and fold gently until everything is evenly coated. Transfer mixture into a lightly buttered 9x9-inch (or similar) shallow baking dish, pressing down to level the top.

In a small bowl, mix remaining 1/4 cup grated gruyère, remaining parmesan (about 1/6 cup), and bread crumbs. Sprinkle this evenly over the top of the gratin and dot with a few small pieces of butter if desired.

Bake in the preheated 375°F (190°C) oven until golden and bubbling around the edges, about 25–30 minutes. If top is browning too slowly, place under broiler for 1–2 minutes, watching carefully to avoid burning.

Remove from oven and let rest 8–10 minutes to set. Serve warm, spooning portions that include artichokes, kale, and roasted romaine.