Preheat the oven to 225°C. Place the beetroot and onion slices upright in a roasting tin and sprinkle half of the oregano, salt and black pepper over them. Drizzle the oil and balsamic vinegar on top of everything.
Roast the beets and onion slices in a hot oven for 25-30 minutes. Turn over occasionally.
While the tin is roasting, prepare the quinoa according to the instructions on the packaging. After about 15 minutes, place the vegan goat cheese slices (if you have any) between the beets and let them roast alongside the tin until golden brown.
Done! Serve the quinoa in wide bowls and pour the oven-roasted mix on top. Garnish with the rest of the fresh oregano.