4 slices good-quality whole grain bread (you can also use rye bread)
1/2 pound pastrami
4 slices Swiss cheese
1/4 red onion, sliced into slivers
8-10 cornichons, sliced in half length wise
2 tablespoons mustard (we used a whole grain mustard, but use whatever you prefer)
1 tablespoon olive oil
Lay two pieces of bread on a flat work surface. Layer mustard, pastrami, cheese, onion, cornichons and mustard on the bread slices, distributing evenly. Place other slices of bread on top of the sandwiches and secure with a toothpick.
To grill the sandwiches, heat your panini press or a large skillet to medium-high. Add olive oil and cook sandwiches for about three minutes on either side.
Slice in half and serve immediately.