Kids-cook: Curried Vegetables

• 2 potatoes
• 2 cauliflower florets
• 2 onions
• 230 gr tomatoes (canned)
• 16 ml vegetable oil
• 5 ml mustard seeds
• 3 gr turmeric
• 3 gr sal bring to (boil)
• 2 gr curry powder
• 2 gr cumin (ground)