A recipe for “luke warm water” ….

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I rate this recipe five stars.
I made some substitutions though for my family. I only used half of the recommended cold water because we’re all on a diet. I doubled the amount of boiling water. Added 5 cups of ice cubes. Let it sit for one hour. Added 2 cups of boiling water. Waited until the water became lukewarm, then took out what I needed. I froze the rest of the water for weeknight baking– it keeps in the freezer just fine.
As someone who once killed a pack of dry yeast by pouring boiling water onto it, this is actually very useful
There might be a reason for this. If they just say ‘lukewarm water’, you might be tempted to just get it from the tap. Warm tap water can leach calcified salt buildup from your heater, which can mess with your rise times (the extra calcium binds to the bicarb in your baking soda and carbon dioxide form the yeast, forming chalk). Also, hot tap water dissolves heavy metals much more easily, and lot of poeple’s pipes still have low levels of chemicals like lead in them (even though they’re marked as “lead free”). As a result, the EPA suggests only using cold tap water for cooking, drinking, and mixing baby formula. Which you then warm up elsewhere.
Giving the amount is kinda dumb though.