Preheat oven to 400 degrees. Scrub the potatoes and dry them and then prick potatoes all over with a fork. Rub the potatoes with canola oil and sprinkle with salt and pepper and place on a baking sheet and bake for one hour or until fork tender. Remove from oven and when the potatoes are cool enough to handle, peel them and cut them into small cubes.
In a large Dutch oven, cook bacon over medium-high heat until crisp. Remove with a slotted spoon to a paper towel-lined plate. Pour the fat from the pot, leaving just one tablespoon in the pot.
Melt the butter in the pot. Add the onions, Montreal Steak Seasoning, salt and pepper and cook over medium heat for 5 minutes, until softened. Add the garlic and continue to cook for one minutes, stirring often.
Whisk in the flour and cook for 1-2 minutes, stirring often. Slowly whisk in the milk and chicken broth followed by the potatoes. Bring the soup to a boil over medium-high heat. Reduce the heat to a simmer and cook until the soup thickens, about 8-10 minutes. Stir in the cheddar cheese and some of the bacon, leaving some extra for topping and continue to cook until the cheese is melted. Season with extra salt and pepper, if desired. Ladle into bowls and top with extra shredded cheese, bacon, chopped chives and sour cream, if desired.