Equipment Needed
- Large skillet
- Cutting board and sharp knife
- Mixing bowls
- Rolling pin
- Pastry brush
- Baking sheet
- Parchment paper
Step-by-Step Instructions
My process always starts with getting the puff pastry out of the fridge so it’s ready to roll. Then, I focus on the filling. In my large skillet, I melt the butter over medium heat. I add the finely chopped onion and cook it, stirring often, until it becomes soft and translucent, about 5 minutes. This step builds a sweet, savory foundation. Next, I add the minced garlic and cook for just 30 seconds until fragrant—any longer and it can burn and turn bitter. The smell at this point is already heavenly.
Now, for the mushrooms. I add all the finely chopped mushrooms to the skillet. They will seem like a huge mound at first, but don’t worry. I sprinkle them with the thyme, salt, and pepper. I cook them, stirring occasionally, for 8-10 minutes. The magic happens here: the mushrooms will release their liquid, and then that liquid will evaporate, leaving behind a deeply browned, concentrated, and intensely flavorful mixture. This is called “cooking out the water,” and it’s the most important step for a rich, non-soggy filling. I let this mixture cool completely in the skillet. A warm filling will melt the pastry and make rolling a sticky disaster.
While the mushroom mixture cools, I prepare the pastry. On a lightly floured surface, I gently roll out the thawed puff pastry sheet just enough to smooth any creases and create an even rectangle, about 10×12 inches. I then spread the cooled mushroom mixture evenly over the entire surface, leaving only a tiny 1/2-inch border along one of the long edges. I sprinkle the shredded mozzarella and grated Parmesan evenly over the mushrooms. Then, starting from the long edge opposite the bare border, I carefully but firmly roll the pastry up into a tight log, using the bare edge to seal the roll. I place the log seam-side down on a parchment-lined baking sheet and pop it into the freezer for 15-20 minutes. This chill firms up the butter in the pastry, guaranteeing clean slices and maximum flakiness.(See the next page below to continue…)