Homemade Falafel with Lemon Tzatziki

1. Pour the chickpeas into a large bowl filled with water; let the chickpeas soak overnight. They will double in size.
2. Drain and rinse the chickpeas and then pour them into a food processor (a blender works, too). Add the onion, shallot, roasted garlic, breadcrumbs, parsley, dill, cumin, coriander, salt, baking powder, and black pepper.
3. Pulse or blend all the ingredients together until a rough, coarse meal forms. Scrape the sides of the processor periodically and push the mixture down the sides. Process the mixture until the ingredients are combined and the texture is soft. Cover the bowl and refrigerate for 1–2 hours.
4. Roll the mixture into 2" balls.
5. Fill a large skillet with 1" of vegetable oil. When the oil is shiny and hot, fry the falafel in batches until they are golden brown on all sides. Remove from the skillet and place the falafel patties on a paper towel-lined plate to drain.
6. For the lemon tzatziki: In a medium bowl, combine all the ingredients. Mix well. Cover and chill until ready to use.

To serve: Add romaine to a piece of pita bread, and then top it with falafel, tomatoes, cucumbers, and red onion. Drizzle with lemon tzatziki, if desired.