In a pan heat oil, add cumene seeds. Add the carrots and sautxe9 for 1 minute.Then add the French beans, sautxe9 and cook covered for few minutes or till the veggies are just done. Add the boiled corn kernels and cook for a few minutes more.Add the mashed potatoes and mix nicely. Now add the masalas- turmeric powder, coriander powder, cumene powder,red chilli powder and Garam masala .Add salt and mix nicely.Lastly add the amchur powder, mix and remove from steam and cool the mixture.