I know everyone is concerned about cholesterol nowadays, but every once in a while I just have to have one of these! Back in the 50's & 60's a local little hamburger joint use to make these. I can just try to explain the technique and you have to follow these steps to get the full impact.

For sauce, in small bowl mix together:
1/2 cup ketchup
1 tablespoon mustard
2 tablespoons brown sugar

Sauce should be tangy and sweet. Let set out on counter for several hours for brown sugar to melt at room temperature.

Slice a yellow onion vertically paper thin. Between waxed paper flatten hamburger patty that has been seasoned with salt and pepper. It should be a good-size patty BUT paper-thin. Fry in a HOT skillet, with a little oil so it won’t stick, till CRUNCHY on both sides. Get a good-size hamburger bun, butter the insides, and toast in semi-hot skillet.

To assemble:
Put patty on bottom bun, then onions, and slather on the sauce.

YUMMY!