Step 1

Place a rack in lower third of oven; preheat to 400°. Heat oil in a large heavy pot over medium-high. Season ½ cup flour with salt and pepper. Add beef and toss to coat; shake off excess. Working in batches as needed to avoid steaming meat, cook beef, turning often, until browned all over, 8–10 minutes per batch. Transfer to a plate.

Step 2

Cook bacon in same pot, stirring often, until brown and crisp. Add ¼ cup water and cook, scraping up browned bits, then add onion, leek, and carrot and cook, stirring occasionally, until vegetables are starting to soften, about 5 minutes. Stir in garlic and parsley and return beef to pot. Add brandy and simmer until liquid is almost completely evaporated, about 1 minute. Add thyme leaves, bay leaf, star anise, broth, and wine and season with salt and pepper; bring to a simmer.

Step 3

Mix 1 Tbsp. flour and 1 Tbsp. butter in a small bowl until smooth; stir into meat mixture. Cover pot and braise in oven until beef is very tender, 1–1½ hours.

Step 4

Melt remaining 4 Tbsp. butter in a large skillet over medium-high heat. Add mushrooms and pearl onions and cook, stirring, until browned, 8–10 minutes. Stir in lemon juice; season with salt and pepper. Add mushrooms and onions to stew, cover pot, and return to oven. Cook until onions are very tender, 25–30 minutes. Let stew cool.

Step 5

Meanwhile, working with one at a time, roll out pastry sheets on a lightly floured surface until about 4” larger than baking dish (use a 2-qt. oval or an 8” square). Place 1 sheet on a parchment-lined baking sheet and chill. Transfer remaining sheet to baking dish. Lift up edge and let dough slump down into dish. Trim, leaving about 1” overhang. Transfer stew to baking dish. Brush edge of pastry with egg.

Step 6

Using a cutter, punch out a circle in the center of chilled pastry. Drape pastry over filling and trim to a 1” overhang. Press edges of dough together to seal and fold overhang under. Crimp edge, then brush top of pastry with egg.

Step 7

Bake until crust is deep golden brown, 30–35 minutes. Let pie cool slightly.

Step 8

Do Ahead: Stew can be made 2 days ahead. Cover and chill.