Tandoori baby potatoes with herb yogurt

from Indian Vegetarin Feast by Anjum Anand

*I would double the potatoes because the tandoor marinade and topping make enough for more potatoes and they taste really good. 

Ingredients

for the potatoes

• 8 baby potatoes
• salt 
• 2 T butter

for the tandoori marinade 

• 2/3 cup greek yogurt
• 1 3/4 t ground cumin
• 3/4 t garam masala
• 1 t ground coriander
• 1/4-1/2 t chili powder
• 1 t paprika
• 3 garlic cloves, peeled and minced
• scant 1/4 oz. gingerroot, peeled weight, grated
• 2 T vegetable oil
• 1 1/2 T lemon juice

for the topping 

• 1 cup greek yogurt
• 1/3 t black pepper
• handful chopped cilantro leaves
• 1/2 onion, minced
• 1 green chile, seeded and minced, or to taste
• 2 T dried cranberries or raisins (optional, if going for sweet/savory)
• 1-2 T milk, if needed 

Directions

1. Peel the potatoes and halve. Bring lots of salted water to the boil in a large saucepan. Add the potatoes and boil for eight minutes. Remove and, when cool enough to handle, use a spoon to scrape out a deep depression so that the potatoes look like boiled egg halves where the yolk has been removed.
2. Mix the ingredients for the tandoori marinade in a bowl. Add one good teaspoon of salt (the marinade only coats the potato so the salt will not seem excessive). Place the potato halves in the bowl, turn to coat in the marinade and leave to marinate for 30 minutes. Mix together all the ingredients for the topping, adding the milk if the consistency seems a little thick, and season to taste.
3. Preheat the oven to 220°C. Place the potatoes, flat side up, on a baking tray and place on the middle shelf of the oven. Cook for 20–25 minutes, or until the marinade looks properly dried. Now turn the potatoes over, move the rack to the top of the oven, and continue to cook for eight to 10 minutes. Turn again and cook for a final eight to 10 minutes. They should be tender by now (check by piercing one of the largest potato halves with a knife).
4. Meanwhile, melt the butter and brush it over the potatoes. Spoon a rounded teaspoon of topping on to each potato half and serve immediately.