Place potatoes in a shallow pot with enough cold water to cover by 1 inch. Bring to a boil over high heat, about 5 minutes. Once a boil is reached, drain immediately and rinse under cool, running water. Set aside.
Heat a 4-quart stockpot over medium heat. Add bacon and cook, stirring frequently, until fat is rendered and bacon is wilted.
Add butter to pot and cook onions, stirring frequently, until translucent, about 5 minutes. Add flour and thyme, stirring well. Let flour cook another 5 minutes.
Add clam juice gradually, allowing the flour mixture to absorb it. Pour in half-and-half slowly, stirring to smooth out any lumps of flour.
Once the cream is warmed through, add the potatoes and clams with their juice. Allow potatoes to finish cooking and chowder to heat through, 5 to 10 minutes or until potatoes are tender. Season with pepper. Divide among serving bowls and garnish with parsley.
Servings: 6