2 15-ounce cans chickpeas (see Recipe Note for dry chickpea version)
1/2 large red onion, roughly chopped (about 1 cup chopped)
4 cloves garlic, roughly chopped
1/4 to 1/2 cup loosely packed parsley
1/4 to 1/2 cup loosely packed cilantro
2 tablespoons olive oil
2 tablespoons lemon juice
2 teaspoons cumin
2 teaspoons coriander
1 1/2 teaspoons salt
2 teaspoons baking powder
1/4 cup all-purpose flour, optional for binding
Preheat the oven to 375°F: Brush or rub a baking sheet with a thin layer of olive oil.
Combine all the ingredients in a food processor, except baking powder and flour: Add the chickpeas, onion, garlic, 1/4 cup parsley, and 1/4 cup cilantro to the bowl of a food processor. Sprinkle the olive oil, lemon juice, and spices over top.
Pulse until the ingredients are mixed: Pulse the food processor 10 or 12 times, until the chickpeas are chopped and all the ingredients are mixed.
Taste the mixture: Taste and add more herbs, spices, olive oil, or lemon juice, if you like.
Add the baking powder: Sprinkle the baking powder and flour, if using, over the mixture.
Continue pulsing until the mixture forms a ball: Continue to mix the chickpeas in pulses, scraping down the sides of the bowl as needed, until the mixture forms a ball when you squeeze it in your hand. You can completely purée the mixture if you like, but I prefer to leave it fairly chunky.
Bake the falafel right away or refrigerate for up to 5 days: The falafel mixture can be transferred to an airtight container and refrigerated for up to 5 days. Refrigerating also helps the mixture firm up and be less crumbly when baked.
Roll the falafel into large balls: Using your hands, scoop up some of the mixture and form it into a ball in your hand. The exact amount doesn't matter — just make sure that all your falafel balls are roughly the same size so they bake at the same rate.
Press the balls into patties: Transfer the falafel balls to the baking sheet and gently press into patties roughly 1/2-inch thick. Pressing the patties increases the surface contact with the baking sheet and makes the baked falafels crispier. If the patties break a little as you press them, just pat them back into shape.
Brush the tops with a little more olive oil.
Bake for 25 to 30 minutes, flipping the falafel partway through: The falafel are fairly delicate (especially if you skipped the flour), so be gentle when flipping them. If one does fall apart, just press it back together with the back of your spatula. When finished cooking, the falafel should be golden brown on both sides and feel dry to the touch, but still give a little when you press the middle.