One-pot orzo with beetroot, thyme and orange

Name: One-pot orzo with beetroot, thyme and orange
Cuisine: European
Ingredients: 300g orzo; 650g beetroot, peeled and grated; a small bunch of thyme, leaves picked; 3-4 cloves of garlic, finely chopped; 1 tablespoon balsamic vinegar; 2 tablespoons good olive oil, plus more for finishing; 1/2 vegetable stock cube; zest of a small unwaxed orange; 4 handfuls of rocket; 100g feta or vegan feta-style cheese, crumbled (optional); a few handfuls of toasted chopped nuts (walnuts, almonds or hazelnuts will all work well); a drizzle of olive oil