Description
This Broccolini au Gratin recipe is a deliciously creamy and cheesy side dish featuring tender broccolini baked in a rich Parmesan and Gruyère cheese sauce topped with golden toasted panko breadcrumbs. With a hint of whole grain mustard and fresh thyme, it offers a perfect balance of flavors and textures, ideal for family dinners or holiday meals.
Ingredients
Units
Scale
Vegetables
- 1 1/2 pounds broccolini, ends trimmed
- 1 large shallot, thinly sliced
- 2 garlic cloves, finely chopped
- 1 teaspoon minced fresh thyme
- 1 tablespoon minced fresh flat leaf parsley (optional)
Cheese & Dairy
- 5 tablespoons salted butter
- 1 1/2 cups whole milk
- 3/4 cup grated Parmesan cheese, plus more for serving
- 1 cup grated Gruyère cheese
Other Ingredients
- 2 tablespoons extra-virgin olive oil
- 3/4 cup Panko breadcrumbs
- 3 tablespoons all-purpose flour
- 1 tablespoon whole grain mustard
- 1/2 teaspoon kosher salt
- 1/2 teaspoon freshly cracked black pepper
- 1/4 teaspoon ground nutmeg
Instructions
- Preheat the oven: Set your oven to 400°F (200°C) and position a rack in the center. This ensures even heat distribution for perfectly baked broccolini.
- Prepare and bake broccolini: Place the trimmed broccolini in a shallow 3-quart baking dish. Toss it with 1 tablespoon of olive oil to coat evenly. Bake for about 10 minutes until the broccolini becomes bright green and slightly tender.
- Toast the panko breadcrumbs: While the broccolini bakes, melt 2 tablespoons of the butter in a small skillet over medium heat. Add the panko breadcrumbs, tossing them to coat in the butter. Cook, stirring occasionally, until the panko turns a golden brown color. Remove from heat and set aside.
- Make the cheese sauce base: In a large skillet, heat the remaining tablespoon of olive oil over medium heat until shimmering. Add the sliced shallot and cook, stirring, for about 3 minutes until softened. Next, add the chopped garlic and stir for another minute until fragrant.
- Create the roux and thicken the sauce: Add the remaining 3 tablespoons of butter to the skillet. Once melted, sprinkle in the flour and whisk continuously until the mixture absorbs the butter and cooks for 1 to 2 minutes. Slowly whisk in the whole milk and continue whisking as the sauce thickens over 4 to 5 minutes.
- Add seasoning and cheese: Stir in the whole grain mustard, kosher salt, black pepper, ground nutmeg, minced thyme, ½ cup Parmesan cheese, and ¾ cup Gruyère cheese. Stir frequently until the cheeses melt completely and the sauce is smooth. Remove the skillet from the heat.
- Combine sauce and broccolini: Pour the creamy cheese sauce over the baked broccolini in the baking dish. Sprinkle the remaining ¼ cup Parmesan and ¼ cup Gruyère evenly over the top.
- Bake the gratin: Return the baking dish to the oven and bake for 25 to 30 minutes, or until the sauce is bubbling and the cheese on top is lightly browned.
- Rest and finish: Remove the gratin from the oven and let it rest for 10 minutes to set. Just before serving, top with the toasted panko breadcrumbs and optional fresh parsley for a beautiful, crispy finish.
Notes
- For a nuttier flavor, try substituting part of the Panko with crushed almonds or walnuts when toasting.
- Gruyère cheese adds great melting qualities and depth of flavor, but Swiss or Fontina could be used if unavailable.
- To make this dish gluten-free, use gluten-free flour and Panko breadcrumbs.
- Leftovers reheat well in the oven or microwave but may lose some crispness on the topping.
- Fresh thyme is preferred for its bright herbal notes; dried thyme can be used in a pinch but use less, about ½ teaspoon.
Nutrition
- Serving Size: 1/6th of recipe (approximately 200g)
- Calories: 320 kcal
- Sugar: 4 g
- Sodium: 400 mg
- Fat: 22 g
- Saturated Fat: 11 g
- Unsaturated Fat: 9 g
- Trans Fat: 0.3 g
- Carbohydrates: 18 g
- Fiber: 3 g
- Protein: 11 g
- Cholesterol: 55 mg
