The Pastrami Rye Sandwich

• Make marmalade: Melt butter with oil in a large heavy frying pan over medium-high heat. Add onions, garlic, sugar, salt, and pepper, stirring well to combine creating a sweet onion broth. Reduce heat to medium and cook, stirring occasionally, until onions have softened and browned, about 20 minutes. Add vinegar or wine. Cook, uncovered, stirring occasionally, until most of the liquid has been absorbed and onions are soft and sticky, about 10 minutes. Let marmalade cool slightly.
• Make the sandwiches: Evenly spread one side of each bread slice with 1/2 tbsp. butter and spread thinly across the breads. Spread the marmalade on the un touched side and then top with pastrami and cheese. Spread the mustard on unbuttered side of remaining 2 bread slices and place each, buttered side up, on pastrami- and cheese-topped slices.
• Heat a large nonstick frying pan over medium heat. Add sandwiches and cook, turning once, until golden brown on both sides and cheese is melted, about 5 minutes total.
• Make ahead: Marmalade keeps up to 2 weeks, covered and chilled.

Trivia

• January 14th is said to be the National Hot Pastrami Sandwich Day.
• Both the dish and the word pastrami originate from the Romanian delicacy pastram? Which translates to pressed meat this means the pastrami is prepared in a way that would be called pressing the meat from which the Yiddish language borrowed it.

Unlike Pastrami Pastram (pressed meat), is a similar but different delicacy.