“Roast”, “roasted” and “baked”
You “roast” meat: here we are talking about cooking it in the oven (en el horno) with the meat being cooked in its own juices or with butter or oil (hablando de carnes que se hacen al horno en su jugo o con aeite). So the English prepare (traditionally, for Sunday lunch), roast chicken, roast lamb (cordero asado) and roast beef (rosbif). You can also roast vegetables. So the English roast potatoes, parsnip (chivivá), sweet potatoes (batata) and nuts,
The word “baked” means something else. The English “bake” fish in the oven. They “bake” salmon and apples. “Baked” often refers to food that is cooked in its skin (se hacen con su piel). Hence “baked potatoes” and “baked apples”.
If you peel and cook the potatoes in the oven they are called “roasted potatoes”. You also “bake a cake”, “bake bread” (hacer el pan en casa) and “bake a pie” (pastel, empanada, tarta).
“Roasted” also has a more colourful (colorista) use: Mr. Rajoy roasted Mr. Sanchez in the debate (Mr. Rajoy desolló vivo a Mr. Sanchez en el debate).