Batate vaagu is a very popular dish among GSB Community, and its more prominent during festivals, weddings etc., as this does not have garlic or onions. Batato in Konkani means Potato and vaagu is tiger. I don't know how this dish derived this name, but I would think the the color and the spiciness this dish gets from the chillies makes it quite obvious to call it 'Vaagu'. There are many different ways to prepare this dish. Some fry/roast coriander seeds along with coconut gratings till brown, and then make a smooth paste along with Byadgi chillies which gives that red color, richness and that fiery look.
The recipe below is pretty easy and its delicious, too.
2 or 3 medium sized potatoes, peeled and chopped into bite size pieces (you can also use boiled potatoes)
1 medium tomato chopped
Salt to taste
Oil for cooking
2 tsp mustard seeds
4 to 5 curry leaves
3/4 cup fresh coconut gratings
2 tsp coriander seeds
4 or 5 roasted red chillies (a combination of regular and byadgi would be best)
1) In a blender, add all the ingredients listed under "For masala/paste" and make a smooth paste using water as needed.
2) Heat oil in a kadai/deep wok. When hot, add mustard seeds and let it splutter, follow by adding curry leaves and chopped tomatoes. Fry the tomatoes till they are mushy and pulpy for about 4 to 5 minutes.
3) Add the chopped potatoes and enough water for the potatoes to cook. If you have boiled potatoes on hand, then, you can use it as well. Mix everything together and cover with a lid and let the potatoes cook thru.
4) When the potatoes are cooked through, add the ground paste, salt and mix again and let it cook well. If its too thick, add water to get a good consistency.
Serve with rice or rotis.