Thinly slice the onions into half moons.
3 large yellow onions
Heat the oil in a large skillet over medium-low heat. Add the onions and a pinch of salt. Cook, stirring every few minutes, for 35 to 40 minutes until deep golden brown and jammy. If they start to stick, add a splash of water and scrape up the brown bits.
1 tablespoon olive oil
Stir in the onion powder and garlic powder and cook for 1 more minute. Let the onions cool completely, then roughly chop.
1 teaspoon onion powder, 1 teaspoon garlic powder
In a bowl, mix the Greek yogurt, mayonnaise, and vinegar. Fold in the caramelized onions.
1 cup plain Greek yogurt, ¼ cup mayonnaise, 2 tablespoons vinegar, salt, black pepper
Season with salt and pepper to taste. Chill for 30 minutes if you have time, then serve.
