Baked Onion Dip

Baked onion dip takes the retro party classic and gives it a golden, bubbling upgrade that makes most cold onion-soup-mix versions seem like an afterthought. Instead of stirring together ingredients straight from the fridge and calling it done, you’re spooning a tangle of sweet onions, mayonnaise, and two kinds of cheese into a baking dish and letting the oven work its magic. What emerges is a hot dip recipe with a burnished top and pockets of melted Swiss that stretch when you drag a cracker through them.

The beauty of baking this dip lies in what heat does to raw onions—they soften and sweeten, losing their sharp bite while their sugars caramelize around the edges of the dish. The Parmesan adds a salty, nutty backbone, while the garlic salt seasons everything just enough without overpowering the mild Swiss. You can make it hours ahead and slide it into the oven when guests arrive, filling your kitchen with the smell of toasted cheese and caramelized alliums. Serve baked onion dip with sturdy crackers or vegetable spears, and watch the dip disappear before it even has a chance to cool.

Ingredients for Baked Onion Dip

• Mayonnaise: This creamy base binds all the ingredients together, providing a rich, tangy flavor and a smooth, spreadable texture. Use one of the best mayonnaise brands since it plays a starring role here.
• Sweet onion: Chopped sweet onion delivers mild, caramelized flavor when baked, adding both sweetness and savory depth without overwhelming the dip.
• Parmesan cheese: A tablespoon of grated Parmesan contributes sharp, nutty notes that enhance the overall flavor complexity of the dip.
• Garlic salt: This seasoning blend adds savory garlic flavor, along with the necessary salt, to balance the richness of the cheeses and mayonnaise.
• Swiss cheese: Shredded Swiss melts beautifully during baking, creating a stretchy, gooey texture while contributing a mild, slightly nutty flavor to the dip.

Directions

Step 1: Mix the dip

Preheat the oven to 325°F. In a large bowl, combine the mayonnaise, onion, Parmesan cheese and garlic salt; stir in the Swiss cheese.

Spoon into a 1-quart baking dish.

Step 2: Bake the dip

Bake, uncovered, until golden brown, about 40 minutes. If desired, sprinkle with parsley. Serve with crackers.

Baked Onion Dip Variations

• Add some heat: Stir in a diced jalapeno or a pinch of cayenne pepper to give the dip a spicy kick that balances the creamy, cheesy base.
• Try caramelized onions: Replace the raw sweet onion with caramelized onions for a deeper, more complex flavor with extra sweetness and richness.
• Mix up the cheese: Swap the Swiss for Gruyère, white cheddar, or a combination of fontina and mozzarella for different flavor profiles and melting qualities.
• Add bacon: Crumble cooked bacon into the mixture or sprinkle it on top before baking for smoky, savory depth.
• Create a crunchy topping: Mix panko bread crumbs with melted butter and sprinkle them over the dip during the last 10 minutes of baking for added texture.

How to Store Baked Onion Dip

Store leftover baked onion dip in an airtight container in the refrigerator once it has cooled to room temperature. The creamy, cheesy dip will firm up when chilled, so you’ll want to let it sit at room temperature for about 15 minutes before serving again or give it a quick reheat in the microwave or oven. Make sure to cover it tightly to prevent the dip from drying out or absorbing other flavors from your fridge.

How long does baked onion dip last?

Baked onion dip will keep in the refrigerator for three to four days when stored in an airtight container. The mayonnaise base means this dip is best enjoyed relatively fresh, so try to use it up within that window for optimal flavor and food safety. If you notice any off smells or changes in texture, it’s time to discard it.

How do you reheat baked onion dip?

The easiest way to reheat baked onion dip is in the oven at 325° for 15 to 20 minutes or until it’s warmed through and bubbly again. You can also reheat individual portions in the microwave in 30-second intervals, stirring between each round to ensure even heating. If the dip seems a bit thick after reheating, stir in a splash of milk or a dollop of mayonnaise to restore its creamy consistency.

Baked Onion Dip Tips

Can you make baked onion dip with other types of onion?

Yes, you can make baked onion dip with several types of onions! Yellow onions are a great all-purpose choice, offering a slightly sharper, more robust onion flavor than sweet onions. Red onions also work well, offering a milder taste with a hint of sweetness and a pop of color in the dip.

What else can you serve with baked onion dip?

You’ll want a lot of dippers, including crackers or toasted baguette slices, for this dip. Baked onion dip pairs wonderfully with other crowd-pleasers, such as Buffalo chicken wings or a charcuterie board loaded with cured meats a2nd cheeses. Add some jalapeno poppers or crispy mozzarella sticks to round out the menu and give your guests appetizer options.