Brush some butter in a grilling pan and grill all the pieces of chicken ham slightly & keep them aside

Caramelized some finely chopped onions

Apply butter on the pieces of the bread. You can customize the quantity as per your choice

Place a single lettuce leaf on the bread slice and then add tomato slices, caramelized onion & top it with a slices of chicken ham and cheese, top it with another slice of bread

Grill the sandwich for 5 minutes & serve hot