In a small bowl, combine the active dry yeast with half of the warm water and let sit for about 5 minutes, until foamy. Meanwhile, in a separate large bowl, mix together the melted unsalted butter, granulated sugar, kosher salt, and the remaining warm water until well combined to create a rich base for your Pizza Hut Cheese Sticks.

Whisk the butter mixture thoroughly, then add the egg yolk followed by the foamy yeast mixture. Gradually stir in the all-purpose flour until just combined. The dough will be slightly sticky but should form a cohesive ball.

Spread the dough out in a greased 9x13 baking dish, ensuring it covers the base evenly. Cover the dish with a clean kitchen towel and let it rest for 15 minutes while preheating your oven to 350°F.

Once rested, brush the surface of the dough generously with melted butter. Sprinkle a generous layer of shredded mozzarella cheese over the top, followed by grated Parmesan cheese and a dash of garlic salt.

Place the baking dish in your preheated oven and bake for 28 to 31 minutes, or until the cheese is bubbly and the top is golden brown.

Allow the Pizza Hut Cheese Sticks to cool for about 10 minutes before slicing them into eight delightful pieces. Serve warm with marinara sauce on the side for dipping.