You can thaw it by putting it in a bowl of hot water (I use hot water from my flask). You can also use a microwave under medium heat in 15 secs increments (to stir) so that the puree don't get too hot
Personally, I prefer to feed my kids warm puree rather than out from the fridge. Again using same method, I put the container under hot water in a bowl to warm the puree.
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