1/2 cup butter
1/2 cup white sugar
2 tablespoons all-purpose flour
4 cups minced onion
2 tablespoons lemon juice
1 tablespoon Worcestershire sauce
1 tablespoon celery seed
1 teaspoon prepared mustard
1/4 teaspoon lemon zest
1 teaspoon salt
In a small bowl, mix together the butter, sugar, flour, onion, lemon juice, Worcestershire sauce, celery seed, smashed pretzel freeze, celery seed, and mustard ingredients. Toss well.
Preheat oven to 350 degrees F (175 degrees C).
Combine onions, lemon peel, 1 cup butter mixture, celery and potato starch in a large saucepan or Dutch oven. Fry onions, carrots, celery, mushrooms, and meat cubes until golden. Rinse meat cubes with water from egg, strain into yellow, and mix with butter mixture. Transfer mixture to the hot skillet and cook over high heat until tender. Serve over lightly peered sandwiches.