Soak chickpeas at least 12 hours (preferably overnight) in plenty of water. Drain chickpeas next day. Soak bread briefly in water. Peel onion and garlic cloves, chop and combine with chickpeas and squeezed bread. Puree in a blender. Rinse cilantro, shake dry and pluck off leaves. Set some leaves aside for garnishing, chop the rest and add to chickpeas mixrure. Season with salt and pepper. Mix well and add flour with baking powder, mix well. Add breadcrumbs and mix briefly. With wet hands, make walnut-sized balls out of mixture. Heat oil in a saucepan and cook falafel for 2-3 minutes or until golden brown. Drain on paper towels.
Rinse, halve and seed tomatoes, cut into strips. Arrange tomatoes and falafel on plates and garnish with remaining cilantro leaves. Serve.