"Déanann sí an seacláid go foirfe."

Translation: She makes the chocolate perfectly.

[Rewjeo]

Since seacláid is feminine, shouldn't we "an tseacláid" or maybe "an sheacláid?"

[scilling]

Yes, it should be an tseacláid since it’s feminine; not genitive; and begins with an S followed by a vowel.