Rinse and pick over the chickpeas. Place them in a large container with a lid and add 1 quart of water. Refrigerate overnight or up to 24 hrs.
Cut a piece of parchment paper the size of your baking sheet and reserve it. Place the baking sheet in the oven (without the paper) and preheat to 375°F.
Drain the chickpeas and place them in a food processor. Add onion, garlic, parsley, cilantro, salt, pepper, cumin, cinnamon, lemon juice and 1 tbsp olive oil. Process until smooth, stopping to scrape the sides as needed.
Using an ice cream scoop or your hands, form small patties with about 2 tablespoons of the mixture at a time. Place them on a cutting board and press down with your hand to get a 1/2" thickness. Brush the tops with 1 tbsp olive oil.
Take the warm sheet pan out of the oven. Place the reserved sheet of parchment paper on it and drizzle it with 1 tbsp olive oil. Lift each patty carefully with a spatula to place it on the oiled sheet.
Bake for 30 minutes, carefully flipping the falafel after 15 to 20 minutes to get both sides browned.
These keep well in the refrigerator for up to 4 days, or in the freezer for several months.