The people of Edinburger, Scotland let me know what they think should go on a burger.
For two Edinburgers:
1/4 cup diced onion
1 tablespoon olive oil
2 tablespoons balsamic vinegar
1/4 cup Scotch whiskey
1/2 cup ketchup
1 pound ground lamb, made into two oblong burgers
2 slices Cheddar cheese
4 thick slices of good white bread
2 tablespoons butter
2 slices tomato
2 pieces of lettuce
In a small saucepan, make whiskey reduction: Saute onion for a couple of minutes in the olive oil. Add balsamic and whiskey and reduce until very moist. Stir into ketchup.
Meanwhile, grill or fry lamb patties, turning once. Spoon whiskey ketchup on top and cover with Cheddar cheese. Finish cooking until cheese melts. At the same time, lightly grill bread on one side only. Butter the grilled side. To serve: Place burgers on the grilled side of the bread. Top with any leftover whiskey ketchup, tomato and lettuce. Place the last two slices of bread on burger, soft side up.