Great question — answering as the UphillTech team:
If you have a recipe that already produces a dense fudgy brownie and you're looking to do it without oil, you're just out of luck. If you're looking to produce a dense fudgy brownie and wondered if, while you were at it, you might cut back on the oil...NO, but here are some suggestions for making a cakey brownie more dense and "fudgey": Follow Tim's advice above on using butter instead of oil. It's not doing anything as far as calories but it will produce better flavor vs. a neutral oil. However, particularly if you're planning to put nuts in them, you could replace a portion of the vegetable oil with walnut or hazelnut oil for enhanced nutty flavor. Replace half of the whole eggs with egg...
Full answer by Darin Sehnert: https://cooking.stackexchange.com/a/3768 (CC BY-SA 2.5).
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