Lentil Patty Melt

Directions

1. Whisk together butter and mayo in a small mixing bowl. Butter each piece of sourdough on only one side.
2. In a food processor, add walnuts, lentils, mushrooms, flour, onion powder, garlic powder, and the Worcestershire sauce. Pulse until the mixture forms a pliable texture that can be shaped into ten patties, roughly the same size and shape as your bread.
3. In a sauté pan over medium to high heat, add oil and onions and cook until deeply golden brown, approximately 20-25 minutes. Reserve hot.
4. Heat oil on either a plancha or in a pan over medium heat. Cook patties on both sides to form a crust.
5. When patties are cooked, place the slices of bread, buttered side down onto the plancha and place one slice of gruyere cheese onto each. Top each slice of cheese with a patty and then divide the caramelized onions evenly between the sandwiches. Top with a second slice of cheese and the remaining slices of bread, buttered side up.
6. Cook until golden brown and crisp with cheese beginning to melt. Carefully flip the sandwiches and cook further until the other side is also golden brown and crisp.
7. Slice sandwiches in half and serve immediately.