Real Onion Dip

Preheat the oven to 425 degrees F.

In a roasting pan, rub the 2 onions in their skins with the 2 tablespoons oil. Bake until squishy soft, turning them once, about 45 Minutes. Cool, peel the onions and set aside.

Meanwhile, finely dice the remaining onion. Preheat a large skillet. Add the remaining oil and heat until hot. Add the diced onion and cook, stirring occasionally, until it begins to lightly brown, about 5 Minutes. Lower the heat to medium-low and continue to cook, stirring occasionally, until golden brown, about 20 Minutes Longer.

Strain the sauted onions through a sieve. Reserve 1/4 cup of the onion oil and let it cool completely. Set aside.

Puree the roasted onions in a food processor. Add the mayonnaise, vinegar, and salt, and pulse until smooth. While the motor is running, drizzle in the 1/4 cup of reserved onion oil until incorporated. Transfer the onion dip to a serving bowl and stir in the scallions. Refrigerate until very thick, about 3 hours or overnight. When ready to serve top with the sauted onions.