Cut peeled russets into 1/3–1/2" sticks for classic frites. Immediately place cut fries in a large bowl of cold water and soak for at least 30 minutes, up to 2 hours, to remove surface starch.

Dry and coat

Drain the potatoes and pat completely dry with clean kitchen towels or paper towels. Toss the dried fries in 2 tbsp cornstarch until evenly dusted; this helps create a crisp exterior. Shake off any excess cornstarch.

First fry (blanch)

Heat neutral oil in a heavy-bottomed pot or deep fryer to 325°F (160°C). Fry the potatoes in batches—do not crowd—until just tender and pale golden, about 4–5 minutes per batch. Remove with a slotted spoon to a wire rack or paper-towel-lined tray and let drain and cool for 10 minutes.

Second fry (crisp)

Raise the oil temperature to 375°F (190°C). Fry the blanched potatoes again in batches until golden-brown and crisp, about 2–3 minutes. Transfer to a wire rack or paper towel-lined tray. While still hot, season evenly with fine sea salt (about 2 tsp total across batches) and freshly ground black pepper.

Finish with truffle & parmesan

While fries are hot, drizzle truffle oil (about 2 tsp total) evenly over the fries and immediately sprinkle with 3/4 cup finely grated Parmesan; toss gently to coat so the cheese melts slightly and adheres. Add chopped parsley if using.

Harissa Garlic Aioli (GF)

Combine 3 tbsp mayonnaise and 2 tbsp Greek yogurt in a small bowl. Add 1 tbsp harissa paste, 2 grated/minced garlic cloves, 1 tsp lemon juice, 1 tsp olive oil, 1/4 tsp salt and 1/4 tsp freshly ground black pepper. Whisk until smooth and homogeneous. Taste and adjust seasoning—add more harissa for heat, more lemon for brightness, or more mayo for richness. Refrigerate at least 15 minutes for flavors to meld; bring to room temperature before serving if chilled.

Assembly & Serve

Arrange a bed of microgreens or arugula on a serving platter if using. Pile the hot truffle-parmesan fries in the center.

Drape thin slices of Prosciutto di Parma over or alongside the fries. The warmth of the fries will slightly soften the prosciutto for a luxurious mouthfeel.

Place the harissa garlic aioli in a small ramekin alongside the fries for dipping. Finish with an extra 2 tbsp grated Parmesan over the fries and a light scatter of chopped parsley.

Serve immediately with lemon wedges on the side for guests who want a bright squeeze.