- 1). Remove the lid from the clean glass mayonnaise jar and set it open side up on a flat surface.
- 2). Line the interior of the lid with a plastic sandwich bag or small piece of plastic wrap.
- 3). Press the raw beef into the plastic-lined lid gently with clean knuckles.
- 4). Cover the lid full of raw beef with another sandwich bag or piece of plastic wrap and pat it lightly to make it stick to the meat.
- 5). Turn the glass mayonnaise jar on its side and roll the flattest part of the jar over the lid to evenly press the raw burger to a uniform shape.
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