Thanks Hong, I think it was about 20 minutes preheating, I have 4 burners stove, to get the bottom heated I used a cast iron griddle, which was partially by each of the four burners. see below photo for the discoloration.
Main, concern I had using it indoor, the stove base got really.
this weekend, I am testing the oven using 5 of colman single burners (10,000 Btu each), I want to see how hot MPO gets by using all 5 buners at 50 % capacity (25000 bt).
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