Martha's take on the popular Saudi Arabian street food, kebab el mirou, uses protein-packed, mild-flavored millet as a binder. The meatballs are skewered with sweet shishito peppers and served with two easy-to-make dipping sauces.
Make the tamarind sauce: Soak tamarind in 1 1/2 cups hot water. Once the tamarind has softened, mash it in the water, then strain in a fine-mesh sieve, pressing on the pulp and scraping the bottom of the sieve to remove any excess pulp. Add the coriander and sugar, season with salt and pepper, and mix well. Set aside.
Make the tahina sauce: Mix tahini, lemon juice, and cayenne in a small bowl along with 6 tablespoons water until smooth; season with salt. Set aside.
Make the kebabs: Place millet in a small skillet and cook over low heat until toasted, about 10 minutes; set aside.
In a food processor, combine carrot, celery, mushrooms, garlic, and dill; pulse to chop into small pieces. Heat 2 tablespoons oil in a medium skillet over medium. Add chopped vegetables, onion, cardamom, cumin, 2 1/2 teaspoons salt, and 1/4 teaspoon pepper. Cook, stirring occasionally, until softened, 8 to 10 minutes. Remove from heat and let cool to room temperature.
In a large bowl, combine cooled vegetable mixture, toasted millet, and ground beef. Form meat mixture into 1 1/2-inch balls and flatten slightly into patties. Thread 2 patties onto an 8-inch skewer, then add a shishito pepper. Repeat with remaining patties and peppers.
Heat remaining 1/3 cup oil in a large skillet over medium. Add kebabs and cook, turning, until browned and cooked through, 3 to 4 minutes per side. Serve kebabs with tamarind and tahina sauces.
If using wooden skewers, soak them in water for 30 minutes before grilling.