Daily Halacha - Shabbat Laws, 21 Iyar 5777

Is it permissible to add mint or lemon to a cup of hot tea?

A secondary vessel (kli sheni) does not cook, therefore it is permissible to add cold milk to a hot cup of coffee. Similarly, it is permissible to add mint or squeeze lemon into a cup of hot tea [Chazon Ovadia 4, p. 330].

Is it permissible to pour hot water from a primary vessel onto black coffee?

There is no cooking after baking. Therefore, it is permissible to pour hot water from a primary vessel (kli rishon) onto coffee, and it is also permissible to add soup croutons to hot soup even in a primary vessel [Shulchan Aruch 318:5, Yabia Omer 8:35].

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