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Deliciously Cozy French Onion Broccoli Cheese Casserole Recipe to Satisfy Your Cravings

Deliciously Cozy French Onion Broccoli Cheese Casserole Recipe to Satisfy Your Cravings - Featured Image
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Learn how to make delicious French Onion Broccoli Cheese Casserole. Easy recipe with step-by-step instructions.

Ingredients

Scale

  • 3 large yellow onions, thinly sliced
  • 2 tablespoons unsalted butter
  • 1 tablespoon olive oil
  • 1 teaspoon salt
  • 1/2 teaspoon black pepper
  • 1 teaspoon sugar (optional, to enhance caramelization)
  • 4 cups fresh broccoli florets (or 1 package frozen broccoli, thawed and drained)
  • 2 cups shredded Gruyère cheese (or Swiss cheese as a mild substitute)
  • 1 cup shredded sharp cheddar cheese
  • 1 cup cooked quinoa or rice (for extra heartiness, optional)
  • 1/2 cup grated Parmesan cheese
  • 1 cup heavy cream or half-and-half
  • 2 tablespoons all-purpose flour (or gluten-free flour if preferred)
  • 1 teaspoon Dijon mustard (adds depth)
  • Fresh thyme or parsley for garnish (optional)

When I first made this, I learned the importance of patience with caramelizing onions — it takes about 20-30 minutes on low heat, but trust me, it’s worth every minute. I also like to add a pinch of sugar to speed up the process and deepen the sweetness, just like my grandma did. For a vegetarian option, this dish stands beautifully on its own, but adding cooked quinoa or rice can make it more filling if you’re serving bigger crowds or want leftovers for tomorrow.

Instructions

  1. Preheat your oven to 375°F. Lightly grease a 9×13 inch baking dish and set aside.
  2. In a large skillet, melt the butter and add the olive oil over medium-low heat. Once melted, add the sliced onions, salt, pepper, and sugar (if using). Cook slowly, stirring occasionally, until the onions are deeply caramelized, about 20-30 minutes. Patience here truly pays off — I’ve learned that rushing this step results in less flavorful onions.
  3. While the onions are caramelizing, blanch the broccoli in boiling water for 2-3 minutes until just tender, then drain and set aside. If using frozen broccoli, make sure it’s thoroughly thawed and drained to avoid excess moisture.
  4. In a small bowl, whisk together the heavy cream, flour, and Dijon mustard until smooth. This mixture will help thicken the casserole and create a luscious texture.
  5. Once the onions are ready, spread the caramelized onions evenly across the bottom of your prepared baking dish. Layer the broccoli over the onions, distributing evenly.
  6. Sprinkle both the Gruyère and cheddar cheeses evenly over the broccoli. If you’re adding cooked quinoa or rice, sprinkle that on top as well for added bulk and flavor.
  7. Pour the cream mixture over the layered ingredients, ensuring everything is coated well. Finish with a sprinkle of Parmesan cheese for that extra cheesy crust.
  8. Place the casserole in the oven and bake uncovered for about 20-25 minutes, or until the top is golden brown and bubbly. I recommend keeping an eye on it after 20 minutes to prevent over-browning.
  9. Remove from oven and let it rest for 5 minutes before serving. Garnish with fresh thyme or parsley if desired. This resting period helps everything set, making it easier to serve clean slices.

This step-by-step process might seem simple, but I’ve found that the magic happens during the caramelizing stage. My tip is to keep the heat low and stir occasionally — rushing this step can burn the onions or prevent them from developing that deep, sweet flavor I love. I’ve made this dish many times, and each time I learn a little more about patience in the kitchen.

Find it online: https://artofeasycooking.com/french-onion-broccoli-cheese-casserole/