Prep work for potatoes is required at least 1 1/2 hours before making soup.
Preheat over to 350'F. Cut pointy ends off potatoes and discard. Cut whole potatoes in 2" long pieces, and place narrow flat sides down onto tinfoil on baking tray. Brush top exposed ends of potatoes with some olive oil, and sprinkle with salt. Bake for 1 hour. Set aside to cool till you can handle by hand.
Scoop soft cooked potato from skins into bowl and set aside. Discard skins.
In large soup pot, pour enough olive oil to cover bottom. Throw in garlic, onion, celery, Garam Masala and Curry Powder. Stir on medium heat till onion becomes translucent and starts to caramelize. Turn temperature down to medium low.
Add the bowl of soft potatoes and mix together. You will end up with a thick paste. Careful not to burn.
Pour the vegetable stock in and stir till all the lumps are dissolved.
Bring to a boil. Turn temperature down to simmer and cover for 15 minutes.
Let soup cool enough that you can ladle into blender.
I find that filling the blender only half full at a time works best. Start with a slow speed or use the pulse button, as warm or hot soup will tend to surge up more in a blender than cold liquids. Be very careful. Puree soup and return to your original soup pot.
Stir in coconut milk and simmer for a least 5 minutes or till ready to serve.