Soaking and squeezing the bread softens it so that it can combine much more easily with the meat.
- 3 1-inch-thick slices stale white sandwich bread, crusts removed (about 4 ounces)
- 2 large eggs, beaten to blend
- 1 pound ground beef chuck (20% fat)
- 1 cup finely chopped mint
- Kosher salt, freshly ground pepper
Grate onion on the large holes of a box grater and squeeze firmly with your hands to release excess liquid. Place onion in a medium bowl.
Working one at a time, hold slices of bread under running water very briefly to soften (be careful not to waterlog or make soggy). Squeeze firmly with your hands to expel the water. Very finely chop bread and place in bowl with onion. Add eggs and mix well. Add beef and mint; season generously with salt and pepper. Mix with your hands until evenly distributed; be careful not to overwork. Portion into 24 balls (about 1 heaping Tbsp. each).
Heat oil in a medium skillet, preferably cast iron, over medium. Working in 2 batches, add meatballs and press down on each one to flatten slightly. Fry until browned and very crisp, about 3 minutes. Turn and fry on other side until browned and very crisp, about 3 minutes. Transfer to a platter as you work. Serve with Tzatziki.
Do Ahead: Meatballs can be formed 1 day ahead. Cover and chill.