Name: In 'n Out Animal French Fries (Copycat)
Prep time: 45 min
Cook time: 20 min
Total time: 65 min
Yield: 4 servings
Ingredients: 1 large onion (, finely chopped (about 1 1/2 cups)); 2 teaspoons butter; Kosher salt; 2 tablespoons plus 2 teaspoons mayonnaise; 1 tablespoon ketchup; 2 teaspoons sweet pickle relish; 1/2 teaspoon sugar; 1/2 teaspoon distilled white vinegar; 4 slices deli-cut American Cheese; 2 lbs russet potatoes (, peeled and cut into 1/4 inch fries)