Caramelized Onion Patty Melts

Steps

1. Slice the onion, tomato and cheddar before you start cooking.
2. Heat half of the canola oil in a large skillet over medium-low heat. Add the onion and about a quarter of the salt and cook, stirring often, until soft and deep golden, 15 to 20 minutes. Move the onion to a plate and wipe out the skillet.
3. While the onion cooks, put the ground beef in a bowl. Add the Worcestershire sauce, the mustard, the garlic powder, the black pepper and the remaining three quarters of the salt, and mix gently with your hands until just combined.
4. Shape the seasoned beef into 4 thin oval patties about the size of a bread slice.
5. Heat the remaining half of the canola oil in the skillet over medium-high heat. Cook the patties 3 to 4 minutes per side until browned and 160°F (71°C) inside. Move them to the plate with the onion and pour off any fat.
6. Lower the heat to medium. Toast 4 slices of the bread in the dry skillet until golden on one side, then flip them toasted side up.
7. Top each toasted slice with half of its share of the cheddar, a beef patty, a quarter of the onion, a quarter of the tomato and the rest of its cheddar, then a plain slice of the bread.
8. Cover the skillet and cook 2 to 3 minutes until the cheese starts to melt, then carefully flip each melt and cook uncovered 2 to 3 minutes more, pressing gently with a spatula, until the bread is crisp and the cheese is fully melted.
9. Let the melts rest 1 minute, cut each in half and serve hot.