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Best Keto Broccoli Cauliflower Au Gratin

The Best Keto Broccoli Cauliflower Au Gratin

The Best Keto Broccoli Cauliflower Au Gratin is a low-carb, incredibly satisfying casserole that transforms humble vegetables into a decadent side dish. It's perfect for anyone seeking a delicious way to enjoy classic comfort food while adhering to ketogenic principles, proving that healthy eating can be exceptionally flavorful and comforting.
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Prep Time 15 minutes
Cook Time 20 minutes
Resting Time 5 minutes
Total Time 45 minutes
Servings: 6 servings
Course: Side Dish
Cuisine: American, Keto
Ingredients Equipment Method Notes

Ingredients
  

  • 1 head broccoli cut into bite-sized florets (about 4 cups)
  • 1 head cauliflower cut into bite-sized florets (about 4 cups)
  • 2 tablespoons unsalted butter
  • 1 small onion finely chopped
  • 2 cloves garlic minced
  • 1 3/4 cups heavy cream
  • 3/4 cup shredded cheddar cheese
  • 3/4 cup shredded Gruyère cheese (or Swiss cheese)
  • 1/4 cup grated Parmesan cheese
  • 1/2 teaspoon salt or to taste
  • 1/4 teaspoon black pepper or to taste
  • 1 pinch nutmeg (optional, but recommended)
Optional Topping
  • Extra shredded cheese
  • fresh parsley sprinkle of

Equipment

  • Large pot
  • Oven-safe skillet or Dutch oven
  • 8x8 inch baking dish (if not using oven-safe skillet)

Method
 

  1. In a large pot, bring salted water to a boil. Add the broccoli and cauliflower florets and blanch for 3-4 minutes until they are tender-crisp. Drain the vegetables thoroughly and set them aside. Overcooking them at this stage will result in a mushy final dish.
    1 head broccoli, 1 head cauliflower
  2. While the vegetables are blanching, melt the butter in a large oven-safe skillet or Dutch oven over medium heat. Add the finely chopped onion and cook until it becomes softened and translucent, about 5-7 minutes. Add the minced garlic and cook for another minute until fragrant, being careful not to burn it.
    2 tablespoons unsalted butter, 1 small onion, 2 cloves garlic
  3. Pour the heavy cream into the skillet with the sautéed onions and garlic. Bring the cream to a gentle simmer, stirring occasionally. Reduce the heat to low and let it warm through for about 2-3 minutes.
    1 3/4 cups heavy cream
  4. Gradually add the shredded cheddar cheese, Gruyère cheese, and grated Parmesan cheese to the cream, stirring constantly until the cheeses are fully melted and the sauce is smooth and creamy. Season the sauce with salt, black pepper, and the pinch of nutmeg (if using). Taste and adjust seasonings as needed.
    3/4 cup shredded cheddar cheese, 3/4 cup shredded Gruyère cheese, 1/4 cup grated Parmesan cheese, 1/2 teaspoon salt, 1/4 teaspoon black pepper, 1 pinch nutmeg
  5. Add the blanched broccoli and cauliflower florets to the cheese sauce in the skillet. Gently toss them to ensure each piece is well-coated. If you’re not using an oven-safe skillet, transfer the mixture to a greased 8x8 inch baking dish.
    1 head broccoli, 1 head cauliflower, 1 3/4 cups heavy cream, 3/4 cup shredded cheddar cheese, 3/4 cup shredded Gruyère cheese, 1/4 cup grated Parmesan cheese, 1/2 teaspoon salt, 1/4 teaspoon black pepper, 1 pinch nutmeg
  6. For an extra cheesy crust, sprinkle a bit more shredded cheese over the top of the casserole. Place the skillet or baking dish in a preheated oven at 375°F (190°C). Bake for 20-25 minutes, or until the sauce is bubbly and the top is golden brown and irresistible.
    Extra shredded cheese
  7. Once baked, remove the dish from the oven and let it rest for 5-10 minutes before serving. This allows the sauce to set slightly, making it easier to serve and enhancing the flavors. Garnish with fresh parsley if desired.
    fresh parsley

Notes

Storing and Reheating Tips: Keep refrigerated for 3-4 days. Reheat in oven at 350°F (175°C) for 15-20 minutes, or microwave on medium power.
Freezing: Cool completely, portion into freezer-safe containers. Keep frozen for up to 2-3 months. Reheat from frozen in a 350°F (175°C) oven for 30-40 minutes.