Preheat the oven to 400 degrees F.
In an oven-safe skillet or a pan over medium-high heat, add the vegetable broth, the quinoa, the black beans, the tomatoes, the red bell pepper, the green bell pepper, the red onion, the garlic, the chili powder, the cayenne pepper, 1 1/2 teaspoons of the sea salt, the black pepper, the cumin, and the oregano, stirring to completely combine it.
Bring the mixture to a boil, then lower the heat to a simmer.
Cover slightly and let the chili cook down until the quinoa is fully cooked, about 20-25 minutes.
Transfer the skillet from the heat and stir again, checking to make sure the quinoa is fully cooked.
Spread the chili into a flat layer.
Mix the vegan milk and the apple cider vinegar together and allow to sit undisturbed for 3 minutes. This will create a vegan buttermilk.
In a large bowl, combine the cornmeal, the gluten-free flour, the baking soda, the baking powder, and the remaining sea salt together.
Add the egg replacer, the vegan butter, the sugar, and the maple syrup to the vegan buttermilk, mixing it slowly to incorporate and then slightly faster to make sure everything is properly mixed.
Pour the wet ingredients into the dry ingredients and mix until fully combined and smooth. Since you are using gluten-free flour, overmixing is not as much of a concern as when using traditional flour. The batter should be thick but pourable.
Stir in the diced jalapeno.
Pour the batter over the chili in the skillet, smoothing it out into an even layer or dolloping it like biscuits.
Bake until a toothpick inserted into the center comes out clean all the way and the batter is fully cooked through, about 30-35 minutes.
Move the skillet to a wire rack and allow to cool for at least 10 minutes.
Slice and serve with the vegan sour cream and the vegan cheese!