The “croque madame” is a French grilled cheese sandwich with ham inside and a fried egg on top. Sounds odd, but it’s SO good. It was my very favorite meal on our pilgrimage to Lourdes a few years back. THEN I realized that the name of the sandwich basically translates to "crispy lady" and I knew it was meant to be a part of our feast day celebration of Saint Joan of Arc. Gruyere is the cheese that’s traditionally used, but swiss works in a pinch.
https://www.foodnetwork.com/recipes/alexandra-guarnaschelli/croque-madame-sandwich-recipe-1922870