Roughly chop the bacon and prepare the vegetables. To begin cooking, heat a large, heavy-bottomed Dutch oven or stock pot over medium heat. Cook the bacon pieces until crispy, then remove and pat dry. Drain excess grease from the pot, leaving approximately 1 tablespoon.
Bring to medium-high heat, then add the onions, carrots, and diced pepper. Cook 5-6 minutes, or until softened and fragrant. Add the garlic and cook one minute more.
Add the stock to deglaze the pot, then add the milk, potatoes, and sweet corn kernels. Simmer, uncovered, for 10-12 minutes or until the potatoes are soft enough to be easily pierced with a fork.
Transfer half of the soup mixture to a blender and puree until smooth, about 30 seconds. Return to the pot and stir to combine, then add the zucchini, thyme, red pepper flakes, salt, and pepper. Cook another 5-6 minutes or until the zucchini is softened, then remove from heat.
To serve, ladle the creamy corn chowder into soup bowls. Garnish with crispy bacon bits, shredded cheese, and additional thyme or red pepper flakes (if desired). Serve immediately and enjoy.