Prepare all ingredients.

Finely chop the onion and sauté in a dry pan to remove moisture. Let it cool, then mix with the patty ingredients and knead well.

Shape the patties into round sizes slightly larger than the bread rolls and flatten them.

Cook the patties in a heated pan until golden brown on both sides. Start on high heat to sear the surface, then lower the heat and cover to cook through.

Cut the cheese slices into pumpkin shapes using a knife. Slice the bread rolls in half and lightly toast them in a pan. Spread mayonnaise evenly on the toasted sides.