Combine the yogurt, water, yeast, carrot, parsley, oatmeal, whole-wheat flour, white flour and salt to a bowl, and using a wooden spoon, carefully stir until the dough forms.
Pour the seeds over the top, then cover and set in the fridge overnight, for at least 8 hours.
When ready to bake, set the oven to 425F and line a baking sheet with parchment. Using a large spoon, divide the dough into 6 buns, and place on the baking sheet.
Place the buns in the oven on the centre tray
For extra crispy buns, place an ovenproof pan in the bottom of the oven, and quickly pour in 3 cups of warm water into it. Immediately shut the door to trap in steam, ensuring the oven shut until the buns are golden for 25-30 minutes