To the bowl of a stand mixer with the dough hook attachment, add yeast and warm water. Let rest for 5 minutes until foamy.
Add warm milk, ¼ cup of melted butter, egg, sugar, and 1 teaspoon salt. Mix on low until well combined.
With the mixer on low, slowly add flour. Knead on medium-low speed until the dough becomes smooth and elastic, about 3-4 minutes.
Place the dough in a lightly oiled bowl, turning it to coat.
Cover the bowl loosely with plastic wrap and let it rise at room temperature until it has doubled in size, about 60-90 minutes.
Spray a 9x13-inch baking dish with nonstick cooking spray. Set aside.
When ready, punch down the risen dough and divide it into 24 equal pieces.
Press each piece into a 2x2-inch rectangle.
Working one dough rectangle at a time, brush half of it with melted butter. Fold the unbuttered side over and place into the baking dish. Repeat with the rest of the dough rectangles. (I placed them in a 6x4 array in the baking dish.)
Brush the tops of the rolls with more melted butter. Loosely cover with plastic wrap and let rise for 30 minutes to an hour, or until doubled in size.
When ready to bake, preheat the oven to 350°F.
Bake rolls for 35-40 minutes, or until golden and puffed.
Once baked, brush with more melted butter and sprinkle with salt. Serve warm.