Molten iron
Once generated, molten iron can be cast into iron plates, but it can also be cast directly into steel plates as well as a number of other iron derivative. Many, but not all, of these casting recipes are more resource efficient than casting to plate and using an assembling machine to make the derivative.
Ingredients: 1× Calcite50× Iron ore
Output: 1 per craft → 1.9/min (single machine, no modules)