Line the baking pan with aluminum foil. In the lined pan, toss the bread cubes with ¼ cup olive oil, cheese, thyme, 1 teaspoon salt and ½ teaspoon white pepper.
Bake the croutons until crispy and browned, about 15 minutes. Remove pan from oven. Transfer croutons on foil to a cooling rack.
Set the oven to Roast 400°F.
In the baking pan, toss fennel and leek with 2 tablespoons olive oil and 1 teaspoon kosher salt.
Roast the vegetables until softened and starting to brown, 30-35 minutes. Remove to a medium mixing bowl and set aside until needed.
Again, using the baking pan, toss potatoes with the remaining 2 tablespoons olive oil and 1 teaspoon kosher salt.
Roast the vegetables until softened and starting to brown, 30-35 minutes. Remove to the mixing bowl with the fennel and leek.
Add broth, cream, remaining 1 teaspoon salt and ½ teaspoon white pepper to blender.
Add all of the roasted vegetables and two strips of cooked bacon.
Select the Soup setting and press start. Once the cycle finishes, add the butter, pulse 4 times then pour soup into serving bowls.
Chop reserved fennel fronds. Sprinkle on soup and top with croutons.
