Place a medium size saucepan on low-medium heat and when hot pour 2 tablespoons of olive oil. Wait for a minute to heat up and add the onions. Sauté for 4 minutes until translucent and soft.
In a separate bowl pour the sautéed onions along with their oil, the minced meat, tomato, parsley, bread crumbs, oregano, salt and pepper. Mix thoroughly and refrigerate for an hour. If you want, you can refrigerate overnight covered with plastic wrap.
Next day, or an hour later, turn the oven grill to 220 degrees Celsius and place your rack in the middle of the oven.
In the meantime, take the mixture from the refrigerator and while cold form into small burger patties and place on a lightly oiled oven proof dish. Place the dish in the oven and cook for 5 minutes. Then flip and cook the other side for 3 minutes. You want nicely charred patties!
Serve in a bun with slices of tomato and cucumber.