1/4 cup unsalted butter, melted and cooled slightly
2 teaspoons Worcestershire sauce
4 dashes hot sauce (like Tabasco)
1 teaspoon white vinegar
1 teaspoon salt
Cut the potatoes into 2.5 centimeter thick fries (almost like wedges!) and place them in a large pot. Cover them with cold water, bring to a boil, and blanch for ten minutes. While the potatoes are blanching, in a large, deep pot over medium-high heat, heat the oil to 350°F (180°C).
Drain the potatoes and immediately submerge them in an ice bath to stop cooking. Drain the potatoes again, lay them out on a baking sheet, and pat dry. Place the dried potatoes in a large bowl, sprinkle with cornstarch, and toss to coat. Working in batches, carefully add the potatoes to the hot oil and fry for 12 minutes, or until golden brown and crispy. During the last two minutes of frying, add the rosemary sprigs to the pot. Remove the potatoes and rosemary from the oil and drain them of excess oil on paper towel. Place them in a large bowl and crumble the fried rosemary over the potatoes, add the salt, and toss well.
While the potatoes are frying, bring a wide, shallow pot of water to a slow, rolling boil and add the vinegar. Crack the eggs into the water and poach them for three minutes. Using a slotted spoon, scoop the poached eggs one by one from the water and place them in a bowl of room- temperature water. Check the doneness of your eggs by gently poking them with your finger. If they feel too soft, return them to the boiling water to cook for another one to two minutes, then again lift them into the bowl of water. Lift the poached eggs from the room-temperature water with a slotted spoon and place them gently on a paper towel to remove any excess moisture.
To assemble, arrange the Thick-Cut French Fries on a platter and top with the cheese curds, poached eggs, and Hollandaise Sauce. Sprinkle with chives and serve family style for sharing.
For the Hollandaise sauce:
Fill a saucepan one-third of the way with water and bring it to a simmer. Find a heatproof bowl big enough to rest on the rim of your pot without the bottom of the bowl touching the water. Off the heat, whisk together the egg yolks and lemon juice in the bowl until the mixture doubles in size. Place the bowl over the simmering water and drizzle in the melted butter while continuously whisking. Add the butter slowly at first—if you add it too quickly, your sauce may break. Once the sauce starts to thicken, you can add the butter a little faster. Continue whisking until the hollandaise is smooth and thickened. Remove the bowl from the pot and whisk in the Worcestershire sauce, hot sauce, vinegar, and salt. If your sauce becomes too thick, add a squeeze more lemon juice to loosen it up. Leave the bowl near the warm surface of the stove but not directly on heat.