1. Prep ingredients
Pre-heat oven to 400. Finely chop onion. Drain and rinse chickpeas. Coarsely grate cucumber; place between paper towels to remove moisture. Separately, coarsely grate carrot. Finely grate all of the lemon zest, then squeeze 1 tablespoon juice into a medium bowl, keeping them separate. Cut any remaining lemon into wedges.
2. Make tzatziki & dressing
In a small bowl, stir to combine yogurt, grated cucumbers, and a generous pinch each of salt and pepper. Into the medium bowl with lemon juice, stir in 2 tablespoons oil and season to taste with salt and pepper. Set tzatziki and dressing aside until ready to serve.
3. Cook onions
Heat 2 tablespoons oil in a medium skillet over medium-high. Add chopped onions and cook, stirring, until lightly browned and tender, about 3 minutes. Stir in 3½ teaspoons garam masala; cook until fragrant, about 1 minute. Transfer to a medium bowl
4. Form falafel
Add chickpeas to bowl with cooked onions. Use a potato masher or fork to mash chickpeas until it forms a coarse paste. Stir in grated carrots, lemon zest, 1 large egg, ¼ cup flour, ½ teaspoon salt, and a few grinds of pepper. Use moist hands to form mixture into 3-inch wide patties.
6. Bake falafel & serve