The Club Recipe

In a small bowl combine mayonnaise, Dijon mustard, whole-grain mustard, minced cornichon (or dill pickle), lemon juice, salt, and freshly ground black pepper. Whisk until smooth and adjust seasoning to taste. Set aside.

Preheat and prep

Preheat a skillet or griddle over medium heat. Lightly butter one side of each sourdough slice (about 1/2 tablespoon total). Keep buttered side out for contact with the pan so buttered sides will brown.

Toast bread

Place the two slices butter-side down on the hot skillet. Toast until golden brown, 2–3 minutes. Flip once if necessary to evenly brown; remove from pan and place on a cutting board buttered-side up.

Spread and layer

Evenly spread about half of the deli spread on the unbuttered side of one slice and the remaining half on the unbuttered side of the other slice. On one slice, layer the Gruyère slices followed by the cooked chicken breast slices, arranging them to cover the bread. On the other slice, layer the Swiss slices followed by the pork belly slices.

Assemble

Place the slice with chicken (cheese-side down) on top of the slice with pork belly so cheeses face the meats and create a double-decker. Add the lettuce leaves and tomato slices on top of the assembled meats, pressing gently so the sandwich holds. If the sandwich feels tall, remove excess tomato or lettuce to keep it manageable.

Final toast (optional)

Return the assembled sandwich to the skillet, buttered sides out, and press gently with a spatula or a heavy pan. Toast 1–2 minutes per side over medium-low until cheese just begins to melt and bread is crisp. If you prefer no additional toasting, skip this step.

Serve

Transfer to a cutting board. Insert toothpicks through the sandwich to stabilize and cut diagonally into two halves. Serve immediately.