Ingredients :

• Red onions — Choose them firm, well-rounded, with a deep violet-burgundy, shiny skin. If the skin is dry and dull, the onion is old — it will be bitter and less juicy when cooked. Two medium onions are the right amount for two people as a generous side.
• Olive oil — Use a standard oil, not your best bottle of cold-pressed extra-virgin olive oil. Those oils don’t handle high heat well — they smoke and turn bitter. An ordinary olive oil for cooking is more than enough.
• Sea salt — A pinch, no more. The salt will speed up the onions’ sweating process and concentrate their naturally sweet flavor. Fine salt works too, but sea salt flakes added at the very end provide a subtle crunchy texture that changes everything.
• Lemon juice — Fresh only. Bottled lemon has a chemical aftertaste that is immediately noticeable in such a simple dish. Half a lemon is enough. Squeeze it just before serving, not during cooking — otherwise, the heat kills the aromas.