In a large pot or Dutch oven, add the bacon and cook over medium-high heat until crisp, about 6 minutes, stirring occasionally. Remove the bacon pieces with a slotted spoon and drain on paper towels, reserving the dripping in the pot.

Add the butter to the pot and heat until melted. Add the onion, celery, and carrot and cook until tender, about 7 minutes, stirring occasionally. Stir in the garlic and cook for 1 minute.

Add the corn kernels, corn cobs (if using fresh corn), potatoes, broth, milk, salt, thyme, and pepper. (For an extra creamy chowder, replace ½ cup of the milk with heavy cream.) Bring to a simmer, reduce the heat to medium-low, and cook until the potatoes are tender, about 15 minutes, stirring occasionally. Remove from the heat. Remove and discard the corn cobs.

Place 2 cups of the soup mixture in a blender and blend until smooth. Return to pot and stir in the cooked bacon. Serve hot, garnishing each bowl with chopped chives and black pepper.