Cook bacon in large Dutch oven over high heat, stirring occasionally, until partially rendered but not browned, about 3 minutes.
Add mushrooms and ¼ cup broth and stir to coat. Cover and cook, stirring occasionally, until mushrooms are reduced to about half their original volume, about 5 minutes.
Add onion, garlic, carrots, and thyme. Let cook, uncovered, stirring occasionally, until onion is softened and fond begins to form on bottom of pot, 3 to 5 minutes.
Sprinkle flour over mushroom mixture and stir until all flour is moistened. Cook, stirring occasionally, until fond is deep brown, 2 to 4 minutes.
Stir in the can of consume and Worcestershire sauce, scraping up any browned bits. Stir in beef and bring to simmer, pressing as much beef as possible below surface of liquid.
Cover pot tightly with aluminum foil, then lid; transfer to oven. Cook for 1 hour.
Remove lid and discard foil. Stir filling, cover, return to oven, and continue to cook until beef is tender and liquid is thick enough to coat beef, 15 to 30 minutes longer.
Transfer filling to a 9 x 14 baking dish. (Once cool, filling can be covered with plastic wrap and refrigerated for up to 2 days.) Increase oven temperature to 400 degrees.
Lay out a sheet of wax paper and unroll the tube of croissants onto this.
Carefully invert this over the dish and peel back the paper. brush with an egg wash for a golden brown crust.
(it’s OK if filling is hot).
Place dish on rimmed baking sheet. Brush with a beaten egg to give a wonderful color.
Bake until filling is bubbling and crust is deep golden brown and crisp, 25 to 30 minutes. (If filling has been refrigerated, increase baking time by 15 minutes and cover with foil for last 15 minutes to prevent over-browning.) Let cool for 10 minutes before serving.