Onion dip is a perennial favorite. From my high school days of powdered soup mix and sour cream or the convenience store tubs that found their way into the college dorm fridge, I have always had a soft spot for the creamy, savory classic – particularly with salty ridged chips. I’ve grown up though, and now I make my own fresh spin. I absolutely love a dip made with sweet and sticky caramelized onions. Truthfully, I love caramelized onions with just about anything. But I’ll be honest, sometimes slicing and dicing all those onions and waiting patiently for them to turn that lovely caramel cover is a just a little more work than I’m ready for. This particular onion dip is the result of a kitchen failure. I had planned a really fancy appetizer for a small dinner party and it was an absolute disaster, but I still had guests coming and not enough time (or energy) to head to the grocery store again. So I surveyed what I had on hand, and I always have onions. But there I was, after cleaning up a mess from my previous fail, not really in the mood for the caramelizing process. I decided to give roasting a try, and boy am I glad I did.
This recipe is easy as can be – simply peel and quarter the onions and let the oven do the work. The onions pick up some lovely sweetness in the slow roasting, but the time in the oven also gives a slightly smoky hint from the char. Let the onions get really soft – a knife should just slide right in – and turn dark brown or black at the edges. I always (always) have buttermilk in the fridge and I love the tangy note it adds, but you could also use sour cream. My favorite sidecar for onion dip is plain, salty chips, but this is also great with corn chips or crackers. This is now a favorite in my entertaining repertoire and it is always vaccumed up – and people always want the recipe.
- 3 medium sweet yellow onions
- 1 Tablespoon olive oil
- 5 - 6 sprigs of fresh thyme, plus 2 teaspoons finely chopped thyme leaves
- salt and pepper
- 1 cup mayonnaise
- ½ cup (4 ounces) cream cheese at room temperature
- ½ cup whole buttermilk
- Preheat the oven to 425 degrees. Line a rimmed baking sheet with parchment or non-stick foil.
- Peel the onions and cut them into quarters. Place them on the prepared pan, then drizzle over the olive oil, coating all sides of the onions with oil. Sprinkle generously with salt and pepper. Place the thyme sprigs on top of the onions, then roast for 50 minutes to an hour until the onions are charred in places and soft throughout. Turn the onions over halfway through the cooking time.
- Cool the roasted onions and remove the thyme stalks. Place the onions in the bowl of a food processor and process until well pureed. Add the chopped thyme leaves, the mayonnaise, cream cheese and buttermilk and process until smooth. Season to taste with salt and pepper. Scrape the dip into a bowl, cover and refrigerate for a few hours to let the flavors meld. The dip will keep for a day.