Hetty McKinnon’s showstopping tater tot casserole is directly inspired by, and strikingly reminiscent of, tortilla española.
2 Tbsp. sherry vinegar or red wine vinegar1½ tsp. Diamond Crystal or 1 tsp. Morton kosher salt, divided1 32-oz. bag tater tots, thawed3 oz. Manchego cheese, shavedWhisk shallot, orange juice, vinegar, 3 Tbsp. oil, and ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt in a large bowl to combine; season dressing with pepper. Set aside.
Wipe out skillet, pour in 2 Tbsp. oil, and reduce heat to medium. Add onion and cook, stirring occasionally and reducing heat if needed, until very soft but without taking on any color, 10–12 minutes. Let cool slightly. Fold onion into egg mixture . Heat 2 Tbsp. oil in same skillet over medium-high. Pour egg mixture into pan and flatten surface with a heatproof rubber spatula to make sure tater tots are mostly submerged. Reduce heat to low; cook, undisturbed, watching edges to make sure egg isn’t getting too brown, until golden underneath and top is only a little runny, 20–25 minutes.