Weeknight Spanakopita

1. FOR THE FILLING: Place spinach and water in large bowl. Cover bowl with large dinner plate (plate should completely cover bowl and not rest on spinach). Microwave until spinach is wilted and decreased in volume by half, about 5 minutes. Remove bowl from microwave and keep covered for 1 minute. Carefully remove plate and transfer spinach to colander. Using back of rubber spatula, gently press spinach against colander to release excess liquid. Transfer spinach to cutting board and chop coarse. Transfer spinach to clean kitchen towel and squeeze to remove excess water. Place drained spinach in large bowl. Add remaining filling ingredients and mix until thoroughly combined.
2. FOR THE PHYLLO LAYERS: Adjust oven rack to lower-middle position and heat oven to 425 degrees. Line rimmed baking sheet with parchment paper. Using pastry brush, lightly brush 14 by 9-inch rectangle in center of parchment with melted butter to cover area same size as phyllo. Lay 1 phyllo sheet on buttered parchment and brush thoroughly with melted butter. Repeat with 9 more phyllo sheets, brushing each with butter (you should have total of 10 layers of phyllo).
3. Spread spinach mixture evenly over phyllo, leaving 1⁄4-inch border on all sides. Cover spinach with 6 more phyllo sheets, brushing each with butter and sprinkling each with about 2 tablespoons Pecorino cheese. Lay 2 more phyllo sheets on top, brushing each with butter (do not sprinkle these layers with Pecorino).
4. Working from center outward, use palms of your hands to compress layers and press out any air pockets. Using sharp knife, score spanakopita through top 3 layers of phyllo into 24 equal pieces. Sprinkle with sesame seeds, if using. Bake until phyllo is golden and crisp, 20 to 25 minutes. Cool on baking sheet 10 minutes, or up to 2 hours. Slide spanakopita, still on parchment, onto cutting board. Cut into squares and serve.
   TO MAKE AHEAD: Filling can be made up to 24 hours in advance and refrigerated. Freeze assembled, unbaked spanakopita on baking sheet, wrapped well in plastic wrap, or cut spanakopita in half crosswise and freeze smaller sections on plate. Bake spanakopita frozen, increasing baking time by 5 to 10 minutes.

TIPS FOR TAMING PHYLLO
Frozen packaged phyllo dough functions as light, flaky pastry in traditional Greek dishes such as baklava and spanakopita and as a ready-made tart crust or wrapper for both sweet and savory fillings. But the tendency of these paper-thin sheets to tear, dry out quickly, or stick together can be maddening. Here are some tips for mastering this delicate dough.
1. To help prevent cracking, phyllo must be kept moist until you’re ready to work with it. The usual approach is to cover the stack with a damp kitchen towel. But it’s all too easy to overmoisten the towel and turn the dough sticky.
2. Because phyllo is so fragile, some sheets crack and even tear while still in the box. Don’t worry about rips, just make sure to adjust the orientation of the sheets as you stack them so that cracks in different sheets don’t line up.
3. When phyllo sheets emerge from the box fused at their edges, don’t try to separate the sheets. Instead, trim the fused portion and discard.