Cook the bacon: Place the chopped bacon in a cold 5- to 6-quart Dutch oven. Set the pot over medium heat and cook for 7 to 9 minutes, stirring occasionally, until the bacon is crisp and the fat has rendered.

Drain the bacon: Transfer the cooked bacon to a paper towel-lined plate with a slotted spoon. Leave about 2 tablespoons of bacon fat in the pot and carefully discard any excess.

Soften the vegetables: Add the onion, celery, and red bell pepper to the pot. Cook over medium heat for 5 to 7 minutes, stirring occasionally, until the onion is translucent and the vegetables begin to soften.

Add the garlic: Stir in the garlic and cook for 30 seconds, until fragrant. Do not let it brown.

Cook the flour: Sprinkle the flour over the vegetables. Stir continuously for 1 minute, until the vegetables are evenly coated and no dry flour remains.

Add the broth gradually: Slowly pour in about 1 cup (240 ml) of the chicken broth while stirring to create a smooth base. Add the remaining broth gradually, scraping the bottom of the pot to release any browned bits.

Add the potatoes and seasonings: Stir in the potatoes, 4 cups (600 g) of the corn, thyme, bay leaf, salt, and black pepper. Reserve the remaining 1 cup (150 g) corn for later.

Simmer the chowder: Increase the heat to medium-high and bring the soup to a gentle boil. Reduce the heat to medium-low and simmer uncovered for 12 to 15 minutes, stirring occasionally, until the potatoes are easily pierced with a fork but still hold their shape.

Blend part of the soup: Remove and discard the bay leaf. Use an immersion blender to blend the soup for 10 to 15 seconds, concentrating on one area of the pot. The broth should become thicker while plenty of whole potato and corn pieces remain.

Add the remaining corn: Stir in the reserved 1 cup (150 g) corn. Simmer for 2 to 3 minutes, until the kernels are tender and heated through.

Add the dairy: Reduce the heat to low: Stir in the whole milk and heavy cream. Heat for 3 to 5 minutes, stirring frequently, until the chowder is steaming. Do not allow it to boil.

Adjust the consistency: If the chowder is too thick, add a small amount of warm broth or milk. If it is thinner than desired, simmer gently for another 2 to 3 minutes, stirring frequently.

Season the chowder: Taste and add more salt or black pepper as needed. The chowder should taste savory and mildly sweet, with a creamy broth that coats the back of a spoon.

Rest before serving: Remove the pot from the heat and let the chowder stand for 5 minutes. It will thicken slightly as it rests.

Garnish and serve: Ladle the chowder into six bowls. Top with the reserved bacon, green onions, cheddar cheese, and additional black pepper as desired.