Cowpoke Sandwich

Ingredients

 * 1 large Onion, sliced thick
 * cilantro and Mexican oregano, dried, crumbled
 * salt and pepper
 * Bread slices, buttered
 * vinegar and water, in equal amounts
 * cayenne pepper, to taste

Directions
Put Onion slices in a bowl. Coat with spices, then cover with water and vinegar mixture. Refrigerate for 8 to 10 hours.

Drain Onion slices, season with salt, pepper and Cayenne. Place between two slices of buttered bread.