Cheesy Broccoli Au Gratin gets a delicious upgrade on the Traeger grill. This creamy, cheesy side brings smoky flavor and a golden crust to your holiday table or weeknight dinner.
Traeger Broccoli Au Gratin
You can prepare the broccoli florets on the stovetop or directly on your Traeger pellet grill. Roasting briefly on the grill adds a pleasant wood-fired flavor; par-boiling is fine if you prefer a milder smoke note. Either way, don’t overcook the broccoli in this first step — you want some bite to remain so the florets hold their shape under the cheese sauce.
If you par-boil the broccoli, rinse it under cool water immediately after draining to halt the cooking process. The broccoli will finish cooking in the sauce while it bakes on the grill.
Why You’ll Love This Dish
- Rich and satisfying – A cheddar blend gives this casserole deep, comforting cheesiness.
- Grill-friendly – Using a pellet grill frees oven space and brings subtle smoke to the dish.
- Vegetables that feel indulgent – Broccoli becomes a centerpiece side rather than an afterthought.
- Simple one-dish assembly – Sauce, broccoli, and cheese all go into a single grill-safe pan.
- Easy to scale – Double or halve the ingredients depending on the size of your gathering.
More easy Traeger recipes and ideas for grilling sides and mains.
Recipe Shopping List
Below are the ingredients you’ll need to make this cheesy broccoli au gratin. Quantities are listed in the recipe card further down.
- Fresh broccoli florets — Fresh is preferred for texture, though frozen can work if dried well.
- Olive oil — A light drizzle to promote roasting and color.
- Salted butter — Forms the base of the cream sauce and adds richness.
- All-purpose flour — Thickens the sauce into a smooth, creamy consistency.
- Diced onion — Gentle savory flavor for the sauce.
- Whole milk — For the creamiest texture; lower-fat milks will work but may be thinner.
- Dry mustard — A touch brightens and balances the cheese.
- Garlic powder — Adds depth without overpowering.
- Salt — To taste; enhances all the flavors.
- Shredded cheddar blend — The primary cheese for a melty, flavorful topping.
How To Make This Recipe
This overview walks through the main steps. Follow the full recipe measurements and timing in the printable card below for the best results.
- Preheat and prepare broccoli — Heat the grill to 375°F. Toss broccoli florets with a little olive oil on a baking sheet and roast 4–5 minutes just to begin cooking and add color.
- Make the sauce — In a medium sauté pan over medium-low heat, melt the butter and sauté the diced onion 4–5 minutes until soft. Whisk in the flour and reduce to low heat, cooking and stirring about 5 minutes to remove the raw flour taste.
- Finish the sauce — Add milk, dry mustard, garlic powder, and salt. Whisk and warm over medium-low heat until the sauce thickens slightly and coats the back of a spoon. Remove from heat.
- Assemble in a grill-safe pan — Spray a large grill-safe baking dish with cooking spray. Transfer the roasted broccoli to the pan, pour the cream sauce over it, stir in three-quarters of the shredded cheese, then sprinkle the remaining cheese evenly on top.
- Grill to finish — Place the pan on the preheated grill and bake 20–25 minutes, until the sauce bubbles, the cheese begins to brown in spots, and the broccoli is tender. Serve hot.
A great addition to any holiday menu or weeknight meal lineup.
FAQ
Fresh broccoli gives the best texture and appearance, but frozen florets are convenient and often uniformly sized. If you use frozen, thaw and pat them dry so excess moisture doesn’t dilute the sauce.
Since the broccoli is mostly pre-cooked, look for a bubbling sauce and golden-brown cheese at the edges and on top. The middle should be hot and the broccoli tender when pierced with a fork.
Cool completely, then transfer leftovers to airtight containers or cover the baking dish and refrigerate. Keep portions in the fridge for up to a week; reheating in the oven or air fryer preserves texture best. Microwaving is fine for a quick fix.
Yes—cauliflower works well and generally requires less pre-cooking than broccoli. Proceed with the same sauce and baking method.
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Serve This With
Smoked broccoli au gratin pairs well with a wide range of mains. Try it alongside fish or seafood, roasted or grilled chicken, pork chops, or beef. For a vegetarian option, serve it over buttered egg noodles or add grilled vegetables and a green salad.
- Pacific Northwest-style clam chowder — A creamy, comforting starter to pair with the gratin.
- Pellet grill pasties — Turn your grill session into a multi-dish feast.
- Smoked chicken thighs — A smoky, savory main that complements the cheesy broccoli.
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Traeger Cheesy Broccoli Au Gratin
Traeger Grilled Cheesy Broccoli Au Gratin is a cheese-lover’s dream. A homemade cream sauce coats fresh broccoli, and a generous layer of shredded cheddar bakes to a bubbly, golden finish—perfect for holidays or a comforting weeknight side.
20 minutes
25 minutes
45 minutes
Ingredients
- 6 cups fresh broccoli florets
- 2 tablespoons olive oil
- ¾ cup salted butter
- ½ cup all-purpose flour
- ¼ cup diced onion
- 6 cups whole milk
- ½ teaspoon dry mustard
- ¼ teaspoon garlic powder
- ½ teaspoon salt, or to taste
- 6 cups shredded cheddar blend cheese
Instructions
- Preheat your grill to 375°F. Place broccoli on a large baking sheet, drizzle lightly with olive oil, and roast 4–5 minutes.
- Melt butter in a medium sauté pan. Add onion and sauté over medium-low heat 4–5 minutes. Whisk in the flour and reduce heat to low, cooking 5 minutes while stirring frequently.
- Add milk, dry mustard, garlic powder, and salt. Whisk to combine and cook over medium-low until slightly thickened. Remove from heat.
- Transfer broccoli to a large, well-sprayed grill-safe baking pan. Pour the sauce over the broccoli, stir in ¾ of the cheese, and top with the remaining cheese.
- Grill 20–25 minutes, until the cheese is bubbling and beginning to brown and the broccoli is tender.
Nutrition Information
Yield: 12 Serving Size: 1
Amount per serving (estimate):
Calories: 483 · Total Fat: 38g · Saturated Fat: 21g · Cholesterol: 101mg · Sodium: 648mg · Carbohydrates: 18g · Fiber: 3g · Sugar: 8g · Protein: 20g
Nutrition data is an estimate. Consult a trusted source for medical or dietary needs.