Toss potato, parsnip and carrot in a baking tray with oil, season to taste and spread out. Bake for 20-25 minutes, or until vegetables are tender. Remove from the oven and cool.
In a large bowl whisk eggs, sour cream and season to taste. Pour mixture into a lined baking pan, add the roasted vegetables and broad beans, top with feta cheese and bake in the oven for 30 minutes or until the centre is puffed and the tops are golden.