# Step-by-Step:
01 - Lay out all four rye bread slices on a clean cutting board or flat work surface, ensuring ready access for assembly.
02 - Spread 1 tablespoon of mustard evenly across two bread slices, covering the entire surface edge to edge.
03 - Distribute half the pastrami (about 4.5 oz) onto each mustard-coated slice, arranging meat in an even pile.
04 - Place the remaining plain bread slices on top to close the sandwiches, pressing gently to adhere layers.
05 - Cut each sandwich diagonally in half for easier handling. Serve immediately with dill pickle slices on the side if desired.