This Canadian classic will soon become a classic at your house.
Cut potatoes into lengths of about ¼" x ¼" x 4". Place in a large bowl, cover with cold water, and refrigerate for about 2 hours.
Meanwhile, heat butter in a 2-qt. saucepan over medium-high heat. Add flour, and cook, stirring, until smooth, about 2 minutes. Add shallot and garlic, and cook, until soft, about 2 minutes. Add stock, ketchup, vinegar, peppercorns, Worcestershire, and salt and pepper, and bring to a boil; cook, stirring, until thickened, about 6 minutes. Remove from heat, and keep gravy warm.
Pour oil to a depth of 3" in a 6-qt. Dutch oven, and heat over medium heat until a deep-fry thermometer reads 325°. Drain potatoes, and dry thoroughly with paper towels. Working in small batches, add potatoes and fry, tossing occasionally, until tender and slightly crisp, about 4 minutes.
Drain on paper towels, and let cool for 20 minutes. Increase temperature to medium-high, and heat oil until it reads 375°. Working in small batches, return potatoes to oil, and fry, tossing occasionally, until crisp and golden brown, about 2 minutes. Transfer fries to paper towels to drain briefly, and then divide among serving bowls. Pour gravy over each serving of fries, and top with cheese curds; serve immediately.