Cheesy Skillet French Onion Pull-Apart Garlic Bread

This pull-apart garlic bread takes the classic French onion soup and turns it into a shareable, cheesy skillet loaf.

A crusty sourdough boule is scored into diamond wedges, slathered with garlic butter, and stuffed with slow-caramelized onions and a blend of Gruyère and mozzarella. Baked until the bread is crunchy and the cheese is molten, it’s an irresistible appetizer or side.

Imagine pulling a warm crusty piece of sourdough and watching an endless stretch of melted cheese and sweet caramelized onions. That’s exactly what this skillet bread delivers. The onions are cooked low and slow until they turn jammy and dark, then tucked into every crevice of the bread with garlic butter and two kinds of cheese.

A quick bake and a final broil give you a golden, bubbling top and a soft, gooey center. It’s a crowd-pleasing starter that feels special but comes together with simple ingredients.

Ingredients

Why this recipe works

Caramelizing the onions slowly in butter with fresh thyme draws out their natural sugars, transforming them into a sweet, savory jam that pairs perfectly with the rich cheeses.

This low-and-slow method is the key to the deep flavor that defines French onion dishes. The long cooking time also softens the onions so they melt into the bread rather than staying crunchy.

Scoring the bread in a diamond cross-hatch pattern maximizes the surface area for the garlic butter and fillings. The cuts allow the butter to soak into the crumb, while the cheese and onions nestle into every pocket. Baking in a cast iron skillet conducts heat evenly, giving the bottom a crispy crust while the top stays golden and the inside becomes molten.

Notes and substitutions

Choose a round, crusty sourdough boule with a sturdy structure—it holds up to the stuffing and baking without falling apart. If you can’t find sourdough, a round artisan loaf works. The onions should be sliced thinly and cooked slowly; don’t rush them. Use a heavy skillet for even caramelization.

Gruyère is traditional for French onion flavor, but you can substitute Swiss or white cheddar. Low-moisture mozzarella provides the stretch. For the garlic butter, use unsalted butter so you can control the salt.

Fresh thyme adds a fragrant note; dried thyme can be used in a pinch. This recipe is vegetarian and can be made gluten-free by using a gluten-free bread loaf.

• Gruyère cheese: Swiss cheese or white cheddar
• Sourdough boule: Any round crusty bread like artisan Italian or French loaf
• Fresh thyme: 1 tsp dried thyme
• Low-moisture mozzarella: Provolone or fontina

Equipment

• Cast iron skillet (10-inch)
• Large skillet for onions
• Chef's knife
• Cutting board
• Mixing bowl
• Aluminum foil