Is this just the Easiest French Onion Pasta Bake – Cheesy, Creamy & Loaded with Flavour

Ingredients

• 340 g Penne Pasta (cooked al dente)
• 250 g Ground Beef (80% lean)
• 250 g Mushrooms (sliced thick)
• 1 large Yellow Onion (sliced thin)
• 3 cloves Garlic (minced)
• 2 Tbsp Olive Oil (extra virgin)
• 2 Tbsp Unsalted Butter (cut into cubes)
• 1 tsp Granulated Sugar (helps caramelize onions)
• 1 tsp Salt (plus extra for seasoning)
• ½ tsp Black Pepper (freshly ground)
• ½ tsp Dried Thyme
• 1 tsp Dried Parsley
• ½ tsp Dried Oregano
• 1 tsp Worcestershire Sauce
• 2 Tbsp Red Wine (optional, for depth)
• 1 tsp Balsamic Vinegar
• 1 tsp Hot Sauce (Tabasco or preferred brand)
• 2 Tbsp All-Purpose Flour (for thickening)
• 2 cup Beef Broth (low-sodium)
• 1 tsp Dijon Mustard
• ½ cup Half-and-Half (or equal parts whole milk and heavy cream)
• ½ cup Parmesan Cheese (freshly grated)
• ½ cup Gruyère Cheese (shredded)
• ½ cup Mozzarella Cheese (shredded)
• 2 Tbsp Fresh Parsley (chopped for garnish)

Instructions

1. Cook the Pasta

   Bring a large pot of salted water to a boil, add the penne and cook according to package directions until al dente, then drain and set aside.

   Time: PT10M

   Temperature: 212°F

2. Prep Aromatics

   Mince the garlic, slice the onion thinly, and slice the mushrooms about ¼‑inch thick.

   Time: PT5M

3. Caramelize the Onions

   In the skillet, add 1 Tbsp olive oil, 1 Tbsp butter, a pinch of salt, a pinch of sugar, and ¼ cup water. Add the sliced onions, cover with a lid, and let steam for 10 minutes. Remove the lid and continue cooking, stirring occasionally, until the onions turn deep golden brown, about 10‑12 more minutes.

   Time: PT20M

   Temperature: Medium heat

4. Sauté the Mushrooms

   In a separate part of the same skillet, add a splash of olive oil and ½ Tbsp butter. Add the sliced mushrooms and sauté until they release moisture and start to brown, about 7‑8 minutes.

   Time: PT8M

   Temperature: Medium‑high heat

5. Brown the Beef

   Push the mushrooms to the side, add the ground beef to the pan, break it up, and cook until no longer pink, about 5 minutes. Sprinkle in dried thyme, dried parsley, and dried oregano; stir to combine.

   Time: PT5M

   Temperature: Medium heat

6. Add Flavor Boosters

   Add the minced garlic and cook for 1 minute. Then stir in Worcestershire sauce, red wine (if using), balsamic vinegar, and hot sauce. Let the mixture simmer for 1‑2 minutes to reduce slightly.

   Time: PT2M

   Temperature: Medium heat

7. Create the Roux and Sauce

   Sprinkle the flour over the meat‑vegetable mixture, stirring constantly for 1‑2 minutes to cook out the raw flour taste. Gradually whisk in the beef broth, scraping up any browned bits. Bring to a gentle boil, then lower heat and simmer for 5 minutes until the sauce thickens.

   Time: PT5M

   Temperature: Medium heat

8. Finish the Creamy Base

   Stir in Dijon mustard, half‑and‑half, half of the grated Parmesan, half of the Gruyère, and half of the mozzarella. Add the caramelized onions back into the pan, then fold in the cooked penne and a splash of pasta water to achieve a silky consistency.

   Time: PT5M

   Temperature: Low heat

9. Assemble and Bake

   Transfer the pasta mixture to a greased 9x13‑inch baking dish. Sprinkle the remaining Parmesan, Gruyère, and mozzarella evenly over the top. Bake in a pre‑heated oven at 375°F for 20 minutes, or until the cheese is bubbly and golden.

   Time: PT20M

   Temperature: 375°F

10. Garnish and Serve

    Remove the dish from the oven, let it rest for 5 minutes, then sprinkle chopped fresh parsley over the top. Serve hot.

    Time: PT5M

Nutrition Facts

Calories

560

Protein

28 g

Carbohydrates

55 g

Fat

26 g

Fiber

3 g

Ingredient Substitutions

• Instead of Penne Pasta: Rigatoni, Ziti
• Instead of Ground Beef: ground turkey, ground pork
• Instead of Mushrooms: cremini mushrooms, baby bella
• Instead of Yellow Onion: white onion, sweet onion
• Instead of Garlic: garlic paste, garlic powder (1 tsp)
• Instead of Olive Oil: vegetable oil, canola oil
• Instead of Unsalted Butter: margarine, ghee
• Instead of Granulated Sugar: brown sugar
• Instead of Salt: sea salt
• Instead of Black Pepper: white pepper
• Instead of Dried Thyme: fresh thyme (1 tsp)
• Instead of Dried Parsley: fresh parsley (1 tbsp)
• Instead of Dried Oregano: fresh oregano (1 tsp)
• Instead of Worcestershire Sauce: soy sauce (1 tsp)
• Instead of Red Wine: extra beef broth (2 Tbsp)
• Instead of Balsamic Vinegar: red wine vinegar (1 tsp)
• Instead of Hot Sauce: cayenne pepper (¼ tsp)
• Instead of All-Purpose Flour: cornstarch (1 Tbsp)
• Instead of Beef Broth: vegetable broth, bouillon cube dissolved in water
• Instead of Dijon Mustard: dry mustard powder (½ tsp)
• Instead of Half-and-Half: whole milk + heavy cream
• Instead of Parmesan Cheese: Pecorino Romano
• Instead of Gruyère Cheese: Swiss cheese
• Instead of Mozzarella Cheese: provolone, fontina
• Instead of Fresh Parsley: dried parsley (1 tsp)

Equipment Needed

• Large Pot
• Skillet or Large Frying Pan
• Baking Dish
• Wooden Spoon
• Ladle (optional)
• Measuring Cups and Spoons
• Chef's Knife
• Cutting Board
• Cheese Grater
• Oven

Critical Steps — Do Not Skip

• Caramelizing the onions to develop deep flavor
• Cooking the flour into a roux without burning
• Baking until the cheese topping is golden and bubbly

Chef Tips from the Video

• Use a high‑quality Gruyère for the best nutty flavor.
• Add a pinch of smoked paprika to the sauce for subtle smokiness.
• For extra depth, replace half the beef broth with a splash of dry sherry.

Troubleshooting

Storage

Refrigerator: Cool in an airtight container for up to 3 days.

Freezer: Freeze portions in freezer‑safe containers for up to 2 months; reheat covered.

Room temperature: Do not store at room temperature for more than 2 hours.

Make-Ahead Tips

• Prepare the sauce up to step 8, let it cool, and refrigerate; bake just before serving.
• Cook the pasta al dente and store it in a sealed bag with a drizzle of oil to prevent sticking.

Frequently Asked Questions