Gerunds and infinitives

There are always more ways to skin a cat, as the saying goes. The same English sentence can (and usually will) have more than one way to formulate in French. And, by the way, the same is true the other way around. Translation between two languages is never a one-to-one relationship of grammar, sentences, or styles.

Commencez par préchauffer -- Start by preheating
Faites votre pâte en mélangeant... -- Make your dough mixing... / ...by mixing... etc.

Hi Adrian,

Commencez par préchaffer  --> Start by to preheat ....  (infinitive)

Faites votre pâte en mélangeant  --> Make your dough / batter / pastry while mixing ....

So in the first construction to preheat before utilisation.

Second construction  gerund of mélanger  (expresses an action simultaneous)

https://www.lawlessfrench.com/grammar/present-participle/

Hope this helps.

Jim