To make the seitan wings, stir together the vital wheat gluten, garlic powder, and salt in a large bowl. 

Slowly stir in the broth, and when the gluten becomes too hard to stir, knead it with your hands until the seitan comes together and forms a ball. 

Bring a large pot of salted water to a boil over high heat. Pull tiny pieces of seitan from the dough ball and drop them in the water. Continue this process until all the dough is used. (The seitan will expand; the smaller the pieces you pull off, the better.) 

Boil the seitan, reducing the heat if needed, for 30 minutes. Drain the pot and let the seitan cool completely. 

While the seitan cools, preheat the oven to 375°F (191°C). 

When the seitan pieces are cool enough to handle, squeeze as much liquid out of them as possible with your hands. Place the wings on a medium baking sheet. Drizzle the oil onto the wings and toss to coat them. 

Bake the wings for 20 minutes, flip them and bake for 20 to 25 minutes more, or until they are brown and firm. 

When the wings are almost done, make the barbecue sauce. In a small saucepan over medium-low heat, whisk together the tomato sauce, vinegar, maple syrup, mustard, brown sugar, onion powder, garlic powder, salt, and cayenne pepper. Bring the sauce to a simmer, reduce the heat to low and simmer for 10 to 15 minutes. Taste and adjust the seasonings. Remove the saucepan from the heat 

When the wings are done, toss them in the barbecue sauce and serve them topped with the chives (if using).