Preheat the oven to 375F. Line a baking sheet with parchment and set aside.
For the salad: In a large pan, toast the millet over medium heat for 3 to 4 minutes, or until the grains start to turn golden brown. Meanwhile, in a small pot, bring 2 cups water to a boil. Add the millet and a pinch of salt, stir, cover, reduce the heat, and simmer for 15 to 20 minutes. Remove the pot from the heat and cover it with a kitchen towel to let the millet steam for 5 to 10 minutes. Gently fluff the grains and let them cool to room temperature.
Meanwhile, combine the cucumbers tomatoes, parsley, lemon juice, olive oil, salt and pepper in a large bowl. Once the millet is nearly cool, add to the bowl and stir well. Season with salt and pepper to taste.
For the falafel: In a food processor, pulse the walnuts until they are fine and crumbly. Add the chickpeas, onion, and garlic, and pulse a few more times. Add the remaining ingredients and pulse until a nice texture is achieved and the ingredients are well combined. Use a tablespoon-size cookie scoop or a tablespoon to scoop out the mixture. Moisten your hands with water or oil and gently roll the mix into balls and place them on the parchment. Repeat with the remaining mixture. Use a pastry brush to brush the tops of the falafel with oil. Bake for about 25 minutes, or until the falafel is golden on all sides, flipping them halfway through.
For the dressing: In a food processor or blender, blend the tahini, parsley, lemon juice and garlic until well combined. Slowly drizzle in water as needed until you reach a pourable consistency. Season with salt and pepper to taste. Store in an airtight container in the fridge for up to 4 days.
Serve the falafel in a bowl with the millet salad, greens, hemp hearts, and a generous drizzle of the tahini dressing. Enjoy!