Every recipe that produces Plastic, compared at 100% clock speed on a single machine.
“Alternate: Recycled Plastic” is by far the fastest, 60.00 items/min in a Refinery against 20.00 items/min for “Plastic”. The catch is that the Rubber it runs on is itself made from Plastic (it also needs Fuel). The two are a pair and neither starts from nothing, so run the partner step first and close the loop once it is turning.
Rates per minute are given at 100% clock speed. Solids are shown in items/min, fluids and gases in m³/min. Output per MW compares the step on its own; it excludes the power used upstream and by extraction.