To roast the squash, preheat oven to 400°F. Using a skewer or tip of a pairing knife, poke several holes around the squash. Place whole squash in a baking dish, and place in the oven. Roast for about an hour, or until it becomes tender to the touch.
Remove from oven, cut in half, and let cool completely.
Meanwhile make the whipped aquafaba. Using 1 15-oz. can garbanzo beans (unsalted if possible) and 1/2 tsp. cream of tartar. Strain a 15-oz. can of garbanzo beans through a fine mesh strainer. Measure the liquid, then reduce on the stovetop by about 1/3. Allow the reduced liquid to cool completely. Add 1/2 tsp. cream of tartar and whip with an electric hand mixer, as you would for meringue. Whip until the mixture reaches the soft peaks stage. Set aside.
In a medium mixing bowl, combine the squash, yogurt, nutritional yeast, salt, pepper, and stevia. Mix until well blended into a smooth batter with small lumps of squash.
Gently fold in the whipped aquafaba. The aquafaba may deflate a little. That's okay. Slowly fold in the flour, adding it by sprinkling it on the batter in small batches. When its all mixed in, you will have a rich batter a little firmer than traditional pancake batter, but not as firm as cookie dough.
Heat a griddle to medium and brush with coconut oil. Using a standard ice cream scoop, scoop the batter on to the griddle. Brush a little oil on the bottom of a spatula, and press each mound of batter a little to form a thick pancake. Be careful that the batter doesn't stick to the spatula. Cook on one side for a couple minutes, then flip over. Press down on each pancake a little more with the spatula, and continue cooking on the other side for a couple more minutes. Depending on how hot your griddle is, you may need to flip the pancakes a couple more times and continue cooking until the batter is cooked all the way through. Various gluten free flours will behave differently in the batter. If you flour has more tapioca starch and root stabilizers, it will make a more dense pancake and therefore require a little more cooking time. But if you use traditional all purpose flour, that may not be the case. Once the pancakes are cooked, remove and enjoy immediately.