🛒 Ingredients

For the caramelized onions:

3–4 large sweet onions, sliced
4 tbsp salted butter
1 tbsp olive oil
1 tsp sea salt
1 tsp coarse black pepper
1 tsp granulated sugar (helps the onions caramelize evenly)

For the meatloaf:

1 lb ground beef
1 cup Italian herb bread crumbs
1 cup milk
1 egg
1 packet (1 oz) French onion soup mix

Additional flavor:

½ cup cooking sherry
½ tsp Worcestershire sauce

For finishing:

4 oz Swiss, Gruyère, or provolone cheese, sliced or shredded
Fresh thyme sprigs (optional garnish)

👩‍🍳 Instructions (Long, Detailed Version)

1️⃣ Caramelize the Onions Slowly

Place the sliced sweet onions into the bottom of a 6-quart slow cooker.
Sprinkle them evenly with sea salt, black pepper, and granulated sugar.

Dot the top with the pieces of butter and drizzle the olive oil over everything.

Cover and cook on LOW for 9 hours.
During this time, the onions will gradually soften, release their juices, and cook down into a deep golden-brown, sweet, caramelized base — the essential flavor foundation of the dish.

2️⃣ Prepare the Meatloaf Mixture

In a large mixing bowl, combine:

ground beef
Italian breadcrumbs
milk
1 egg
French onion soup mix

Use clean hands or a sturdy spoon to mix until everything is fully incorporated, but avoid overmixing to keep the meatloaf tender.

Shape the mixture into a loaf that will fit comfortably into your slow cooker.

3️⃣ Build the Flavor in the Crockpot

Once the onions have caramelized, pour the cooking sherry and Worcestershire sauce directly over them.
These liquids help deglaze the onions, enrich the broth, and infuse the meatloaf with deep flavor as it cooks.

Gently place the shaped meatloaf on top of the onion bed.

4️⃣ Cook the Meatloaf

Switch the slow cooker to HIGH and cook for 3 hours, or until the meatloaf reaches an internal temperature of 160°F (71°C).

As it cooks, the meatloaf will release juices that combine with the onions and sherry, creating a rich, savory sauce.

5️⃣ Add the Cheese

Once the meatloaf is fully cooked, lay slices of Swiss, Gruyère, or provolone cheese over the top.

Cover again and cook for 20–30 minutes on HIGH until the cheese is:

melted
bubbly
lightly golden around the edges

The contrast between the creamy cheese and the sweet, deeply flavored onions is what makes this dish unforgettable.

6️⃣ Serve

Slice the meatloaf and serve each portion generously topped with caramelized onions and spoonfuls of the savory onion sauce from the bottom of the slow cooker.

Finish with a sprig of fresh thyme for aroma and a pop of color.

Serve with: