Bring a large pot of water to a boil, once water is boiling add in potatoes and cook until tender. Strain potatoes from pot and set them aside in a bowl.
In a large pot, over medium to high heat, add butter, once butter has started to melt add in chopped carrots, celery, and onion. Season vegetables with 3 teaspoons of Montreal Steak seasoning. Cook until onions are translucent.
Add water and chicken base, bring is a boil. Let it cook over medium heat for 10-15 minutes. Add cream or milk to the pot and then stir in flour mixture. Bring mixture to a boil, reduce heat to medium and cook for 10 minutes.
Add in potatoes and cubed chicken, season with salt and pepper and add an additional 1-2 teaspoons of Montreal Steak seasoning. Let it simmer 15 minutes, until the soup starts to thicken.
While soup is cooking prepare biscuits.
Preheat oven to 415 degrees.
In a medium mixing bowl combine flour, baking powder, sugar, cream of tartar and salt, sift together. Using a pastry blender or your fingers, cut in the butter until mixture resembles coarse crumbs.
Add in milk and using a fork or spoon, stir until dough starts to cling together.
Gently flour your counter, then place dough on floured surface and briefly knead until dough is mostly smooth. Roll out dough to 1/2 inch thickness. Cut out biscuits, I use a round 2 1/2 inch biscuit cutter.
Once soup is done cooking, place 8 biscuits directly on top of the soup. Place the entire pot in the oven and bake for 15 minutes.
If you don’t have a pot you can stick in the oven, just bake the biscuits on a baking sheet for 10-12 minutes and then place on soup immediately when they are done cooking.
Remove from oven and let it sit for 5-10 minutes to cool, then serve.