Step 1

Heat oil in a large skillet over medium heat. Add onions and shallots. Sprinkle with salt and pepper and cook, stirring occasionally until the onions have started to soften and turn slightly brown, about 20 minutes. Turn the heat down to low and continue to cook, stirring occasionally so that they don’t cook too much. Continue to cook until they are a dark brown but not black, about 40 minutes.

Step 2

Remove from heat and finely chop.

Step 3

Add slightly cooled onions to a large bowl and add sour cream, yogurt, lemon juice and garlic. Salt and pepper to taste.