What temperature is best for baking beef Wellington?

The first time I attempted the dish, I baked at 350 until internal temp of beef hit 145; however, the pastry was too dark and had a slight charred flavor. The second attempt baked at 290 until 145 internal; however, on that attempt, the pastry failed to cook and was doughy.



Chef K. January 7, 2012
If your goal is to have a slightly more cooked meat, the best thing to do would be to sear or grill the beef before hand, let it cool completely or at least return fully to room temperature and then cover it in the puff pastry and bake it, this will help you get a finished product that will be around medium instead of medium rare, without charring your pastry.
Chef K. January 7, 2012
Also by letting it cool before wrapping the pastry will keep the pastry from getting soggy, if you wrap it hot the pastry will get wet when baking
Merrill S. January 7, 2012
Puff pastry cooks best at a fairly high heat -- as high as 425, in fact. Beef Wellington is usually served medium-rare, which means removing the roast from the oven when the meat registers an internal temperature of about 125, rather than 145 (keep in mind the temperature of the meat will rise an additional 10 degrees or so as it rests) -- if you're aiming for a more well-done roast, your pastry is likely to overcook. You can try covering the pastry with foil towards the end to keep it from browning too much, or simply cook your meat to a slightly lower temperature.
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