Combine rice, 1 cup water, and a pinch of salt in small saucepan. Bring to a boil, cover, reduce heat to low, and cook until water is absorbed and grains are tender, 15 to 18 minutes. Stir lime zest into cooked rice and set aside, covered.

Combine garlic, just half the lime juice, tamari, vinegar, sugar, just 1 tsp oregano, 1 tsp paprika, 1 tsp cumin, and 1 tbsp vegetable oil in large bowl and whisk marinade. Add sliced seitan, toss to coat, and let marinate for at least 10 minutes.

Stir together remaining lime juice, radish, cilantro, 2 tsp olive oil, and a pinch of salt and pepper in medium bowl.

Wrap tortillas in clean dish towel and warm in microwave to soften, 15 to 30 seconds. Heat 1 tbsp vegetable oil in large nonstick skillet over medium-high heat. Add marinated seitan and any remaining marinade and cook until seitan is crispy in places, 4 to 6 minutes. (TIP: You can also wrap tortillas in foil and place in 400°F oven until heated through, 5 to 6 minutes.)

Divide warm tortillas between plates and top with lime rice, seitan asada, and radish salsa. Dollop tacos with sour cream. ¡Buen apetito!

For 4-serving meal, double all ingredients except water in step 1; use 1⅓ cups water. You may need to cook in batches, in larger cooking vessels, or for longer cook times. Follow visual cues in 2-serving recipe.