2 large yellow onions, or 3 medium
2 T unsalted butter
1/8 c vegetable oil
1/4 t ground cayenne pepper, or to taste
1 t kosher salt, or to taste
1/4 t freshly ground black pepper
1/4 t white pepper, freshly ground if possible
1/4 - 1/2 t dried thyme
4 oz cream cheese, at room temperature, light is fine
1/2 c yogurt, lowfat is fine
1/4 - 1/2 c mayonnaise (as usual, we recommend Blue Plate or Duke's)
onion salt to taste, optional
1. Cut the onions in half and then slice them into 1/8-inch thick half-rounds. (You will have about 3 cups of onions.) Heat the butter and oil in a large saute pan over medium heat. Add the onions, cayenne, salt and pepper, and saute for 10 minutes. Reduce the heat to medium-low and cook, stirring occasionally, for 20 more minutes until the onions are browned and caramelized. Allow the onions to cool.
2. Place the cream cheese, sour cream and mayonnaise in the bowl of an electric mixer fitted with the paddle attachment and beat until smooth. Add the onions and mix well. Taste for seasonings. Depending on how much bite your onions have, you may need to add onion salt or granulated onion at this point. Depending on how dense you want the finished product, you can mix at a medium high speed for a few more minutes to get it nice and airy. This can be refrigerated until needed in an air-tight container, but take it out of the fridge ahead of time so that you can serve at room temperature.