Leftover Prime Rib Stroganoff
2 TB unsalted butter, divided
1 TB extra-virgin olive oil
1 lb assorted fresh wild mushrooms (or a mixture of white and baby bellas) such as chanterelle, oyster, crimini and stemmed shiitake
Coarse kosher salt
1/4 dry vermouth or dry sherry
1/4 cup cream fraiche
1 1/2 pound leftover prepared prime rib, cubed
1 cup thinly sliced shallots (about 4 large)
1 TB all purpose flour
1 tsp tomato paste
1 cup beef broth,
1/2 tsp Hungarian sweet paprika
1/4 cup sour cream
2 Tb chopped Italian parsley
16 oz box farfalle pasta,cooked al dente
Melt 1 tablespoon butter with 1 tablespoon olive oil in large nonstick skillet over medium heat. Add sliced wild mushrooms to skillet; sprinkle with coarse kosher salt and pepper and sauté until mushrooms release juices, about 6 minutes. Increase heat to medium-high; sauté until mushrooms are tender and brown, about 4 minutes longer. DO AHEAD: Can be made 2 hours ahead. Remove from heat. Let stand at room temperature.
Add vermouth or sherry to mushrooms and boil until almost evaporated but still moist, scraping up browned bits, about 1 minute. Stir in crème fraîche; remove from heat. Season to taste with coarse kosher salt and pepper. Cover; set aside.
Melt remaining 1 tablespoon butter in another large nonstick skillet over medium-high heat. Working in batches, add beef pieces to skillet and sauté just warm, about 30 seconds per side. Transfer beef to plate; sprinkle with coarse salt and pepper. Add sliced shallots to same skillet, reduce heat to medium, and sauté until golden brown and tender, about 4 minutes. Stir in flour and tomato paste (mixture will clump). Add broth and paprika and whisk to blend, scraping up browned bits. Simmer until sauce thickens slightly, about 2 minutes. Season sauce to taste with coarse kosher salt and pepper. Remove from heat; cover and keep warm.
Add prime rib and any accumulated juices to shallot mixture in skillet; bring to simmer, stirring occasionally, then stir in sour cream. Remove from heat. Season to taste with coarse salt and pepper. Rewarm mushroom mixture over medium heat.
Add beef mixture to mushrooms and stir to combine. Divide pasta into 4-6 bowls and spoon beef mixture over. Sprinkle with parsley and serve.