When making essence for tea before shabbos one pours boiling hot water over a tea bag to make the essence. If I also put lemon with the tea bag and then pour the hot water over it thereby cooking the lemon juice together with the tea bag, can I just use this tea lemon essence on shabbos in a regular manner like regular essence? Just pour the hot water over the warm essense without using another cup.
The tea essence, including the lemon juice, is considered to have been cooked before Shabbos.
Nevertheless, one should not pour hot water on Shabbos directly from an urn onto the cold essence, but only pour from the urn into a cup, and from the cup onto the essence. This is out of concern for the opinion that although a liquid has been cooked, it can be cooked again after it has cooled.
If the essence is still pleasantly warm, one may pour directly onto the essence from the urn.