I followed a Jaime Oliver recipe for curry, which started with grating onion, ginger and garlic. I liked the curry, but grating an onion is a miserable job. He said that technique unlocked the onion’s ‘sweetness’. How much difference do you think I’d notice if I used a food processor?
The more you cut an onion, the more cell walls you bust open, releasing more flavor. Grating works well for this, but a food processor will do a fairly good job, as would a grinder or mortar and pestle.
When I make curry, I usually just dice the onion, though, unless it’s supposed to be particularly onion forward, then I’m going to be using the mortar and pestle.