Start by preheating the oven to 200C.
Then add all the ingredients (minus the spinach) into a baking dish and stir until the tomato paste has dissolved into the broth.
Cover with aluminium foil and bake for 40 minutes, or until the orzo is al dente and the liquid has evaporated.
Stir about halfway through cooking if needed.
Remove from the oven after 40 minutes and add in the spinach, giving it a stir until it wilts.
Then serve.
