In a large pot or Dutch oven over medium heat, cook the diced bacon for 8-10 minutes, or until crispy. Using a slotted spoon, transfer the cooked bacon to a paper towel-lined plate. Reserve about 1 tablespoon of bacon grease in the pot, discarding the rest.
Add the onions and cook for 3-5 minutes, or until softened. Add garlic. Cook for 1 minute.
Whisk in flour and continue cooking, stirring constantly for 1 minute. Slowly drizzle in chicken broth and milk. Whisk until no flour lumps remain.
Add potatoes. Cover and simmer for 15-18 minutes, or until potatoes are fork-tender.
Add creamed corn, sweet corn, salt, pepper, and crushed red pepper flakes. Stir to combine.
Carefully transfer ½ of the soup to a blender and blend until smooth. (Be careful, the liquid will be hot.)
Return the blended soup to the pot. Add half of the cooked bacon. Stir to combine and cook for 3-5 more minutes, or just until heated through.
Serve hot, garnished with chives or green onions and the remaining bacon.