This French onion dip has been a party staple in my kitchen for years. I first developed this version on a busy afternoon when I wanted the deep, sweet flavor of caramelized onions but also wanted a lighter, fresher base than straight sour cream. The result — a velvety dip with sweet, deeply flavored onions folded into a tangy base of Greek yogurt, sour cream, and a touch of mayonnaise — became an instant favorite. It’s rich without feeling heavy, with a rounded savory-sweet onion note and a bright finish from fresh chives and cracked black pepper.

I discovered the balance in this recipe after several batches where the onions were either under-caramelized or the dip was too tangy. Patience caramelizing the onions makes all the difference: low and slow until they reach a deep golden color gives the dip its signature sweetness and complexity. Over the years I’ve served this at backyard gatherings, holiday appetizer boards, and casual weeknight sandwiches — it’s versatile, forgiving, and reliably devoured.

Ingredients

• Butter and olive oil: Use 1 tablespoon unsalted butter and 2 tablespoons extra-virgin olive oil to gently caramelize the onions. The butter adds flavor and the oil prevents burning; use a good-quality olive oil (e.g., California extra-virgin) for best aroma.
• Yellow onions: Two large yellow onions, finely chopped. Yellow onions are ideal because their natural sugars caramelize beautifully; choose firm, dry onions without soft spots.
• Greek yogurt: 1 cup plain Greek yogurt (full-fat or 2% for creaminess). Greek yogurt lightens the dip while contributing a tangy backbone and extra protein.
• Sour cream: 1/2 cup for richness and the classic creamy profile expected in this style of dip. If you prefer tangier, use cultured sour cream.
• Mayonnaise: 1/2 cup to add silkiness and mouthfeel. Use a quality mayonnaise (e.g., Hellmann’s/Best Foods) for stable emulsion and consistent flavor.
• Garlic and chives: 3 garlic cloves, minced, and 2 tablespoons fresh chives, finely chopped. Garlic gives depth; chives deliver a mild oniony brightness and color contrast.
• Seasoning: 1 teaspoon kosher salt and 1/4 teaspoon freshly cracked black pepper (adjust to taste). Freshly cracked pepper elevates the aroma and adds a little bite.

Instructions

Caramelize the onions:Heat 1 tablespoon butter and 2 tablespoons olive oil in a wide sauté pan over low heat. Add the finely chopped onions and stir to coat. Cook low and slow, stirring every few minutes, for about 30 minutes. Look for a deep golden-brown color and a jammy texture — the onions should smell sweet and slightly nutty. If the pan starts to stick, add a tablespoon of water and continue cooking. Remove to a bowl and cool completely; this can be done a day ahead and refrigerated.Prepare the base:Into a medium mixing bowl add 1 cup plain Greek yogurt, 1/2 cup sour cream, and 1/2 cup mayonnaise. Whisk until smooth to create a uniform base. This combination keeps the dip creamy while lowering overall fat versus an all-mayo or all-sour-cream base.Flavor and assemble:Add 3 minced garlic cloves, 2 tablespoons chopped fresh chives, and 1 teaspoon kosher salt to the yogurt mixture. Stir until evenly distributed. Fold in the cooled caramelized onions, reserving a small spoonful for garnish. Taste and adjust seasoning with more salt and 1/4 teaspoon fresh cracked black pepper as desired. Refrigerate for at least 30 minutes to allow flavors to meld.Finish and serve:Before serving, stir briefly and transfer to a serving bowl. Sprinkle reserved caramelized onions and a pinch of chives on top for visual appeal and an extra hit of flavor. Serve with potato chips, pretzel thins, pita chips, or raw vegetables.

Storage Tips

Store leftovers in a sealed container in the refrigerator for up to 5 days. To maintain the best texture, press a piece of plastic wrap directly on the surface of the dip before sealing the lid to minimize air contact. If you make extra caramelized onions, cool them completely and place in freezer-safe bags, removing as much air as possible; they’ll keep for about 3 months. To reheat frozen onions, thaw in the refrigerator overnight and warm gently in a skillet over low heat before adding to the base. When serving chilled dip after refrigeration, stir and taste again — you may need a pinch more salt or chives to brighten the flavors.

Ingredient Substitutions

For a richer profile, swap the Greek yogurt for full-fat crème fraîche in a 1:1 ratio. For a lighter version, use low-fat Greek yogurt and reduce mayonnaise to 1/4 cup, replacing the remainder with an additional 1/4 cup yogurt. If you're dairy-free, use a plant-based mayonnaise and a thick, strained dairy-free yogurt alternative, though texture and tang will shift slightly. If you prefer an extra savory punch, fold in 1 teaspoon of Worcestershire sauce or 1/2 teaspoon of soy sauce (gluten-free tamari if needed) to deepen umami without overwhelming the onion sweetness.

Serving Suggestions

Serve this with sturdy kettle-style potato chips, pretzel thins, pita wedges, or a colorful tray of crudités — carrots, bell peppers, cucumbers and celery. For a party spread, place the dip in a shallow bowl and surround with an assortment of dippers at varying textures: crisp chips, soft toasted pita, and crunchy vegetables. Garnish with extra caramelized onions and a scatter of chopped chives for an attractive presentation. It also shines spooned onto warm burgers or used as a spread for grilled cheese sandwiches for a grown-up twist.

Cultural Background

While rooted in the flavors of classic French onion soup, this chilled onion dip is an American-born adaptation designed for snack tables and casual gatherings. The technique borrows the hallmark of French cuisine — slow-cooked onions to develop sweetness and depth — but transforms it into a creamy cold accompaniment suited to chips and casual entertaining. Over decades, this style of dip became ubiquitous at parties and potlucks, cherished for its comforting, familiar flavors and effortless crowd appeal.

Seasonal Adaptations

For summer, keep the dip light by using low-fat Greek yogurt and topping with fresh herbs like chives and parsley; serve with crisp seasonal vegetables. In fall and winter, enhance warmth by stirring in a pinch of smoked paprika or a teaspoon of finely chopped thyme to echo seasonal roasting flavors. Holiday versions can include a tablespoon of caramelized shallots in addition to onions, or a swirl of flavored oil on top for a decadent finish.

Meal Prep Tips

Make the caramelized onions up to 3 days in advance and refrigerate in a sealed container. On the day you’ll serve, whisk together the yogurt, sour cream and mayo, then fold in the onions and chill for at least 30 minutes. Portion into small single-serving containers for grab-and-go snacks, or arrange into a large bowl for entertaining. Use shallow containers for faster chilling and to keep the dip at a safe temperature if set out briefly at room temperature during a party.

There’s a simple joy in watching a chip scoop up a ribbon of sweet onion and creamy base — it’s the kind of small culinary pleasure that brings people together. Make this your own by adjusting the tang and chive level; once you find your preferred balance, you’ll be turning to this recipe whenever guests gather.