Poutine (Fries, Cheese Curds and Gravy)

Bake. For the Gravy: Melt butter in a mid-sized saucepan over a medium-high flame till foaming. Beat in flour and cook, mixing the whole time, till golden blonde, around 2 minutes. In a steady stream, gradually beat in stock. Bring to the boil, reduce to a simmer, and cook till reduced to 2 cups, 10 to 15 minutes. Take out from heat, mix in vinegar, and add salt till it tastes right. For the Fries: Put potatoes in a big bowl plus cover completely using cold water. Let soak for no less than 1 hour, or, alternatively, tip off the liquid water and rinse again, changing water till it runs completely clear. Tip off the liquid potatoes and dry well with paper towels. Heat oil in a big Dutch oven or wok to 175°C (177°C). Working a batch after another, add potatoes and cook, mixing and turning often till pale blonde, around 5 minutes. Move potatoes to a paper towel-lined baking tray. (For crispiest fries, see note around adding a freezing step.) Heat oil to 220°C (218°C). Add potatoes and cook, mixing and turning often, till deep golden brown, around 3 minutes. Move to paper towel-lined bowl and add salt till it tastes right till it tastes right. Reheat gravy over a high flame till hot. Put fries in a shallow bowl or dish, top well with cheese curds, and ladle on gravy. Scatter with minced chives (if-you-like). Eat at once.