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the 8x8 should be fine. Might need a couple more minutes baking time as they'll be thicker. good luck!
hardlikearmour is a trusted home cook.
2 options: go with the 8x8 for thicker brownies or use some heavy duty foil to create a 9x9 from the 9x13. See: http://food52.com/blog... BUT fold one end of a large sheet over several times to make it sturdy, then line the pan with the foil so the sturdy part makes the 4th wall to prevent batter leakage.
They'll be thicker but glass will make them bake faster, so cooking time might be the same - I'd just watch them carefully.
You could increase all the ingredients by about 45% - 1 1/2 times the recipe amount should be close enough.
Always decrease the oven temp by 25 degrees when using a glass baking pan. Bake for the same amount of time but watch just in case the bake faster.
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