Season steaks generously with salt and pepper. Heat 1 tablespoon of vegetable oil in a large skillet, over medium high heat, until shimmering. Add steaks and cook, turning occasionally, until browned and cooked to the desired temperature (130°F for medium-rare). Remove from pan and reserve.

Lower heat to medium. Add remaining oil and 2 tablespoons of butter. Once butter is melted, add the mushrooms and cook - stirring frequently - until mushrooms have released their liquid and are starting to brown, about 8 minutes. Add the remaining butter and the onions, cooking until the onions are soft, about 4-5 minutes. Season with salt and pepper.

Add the flour and paprika and stir to combine. Then, add the brandy and cook - scraping the browned bits from the bottom of the pan - until mostly evaporated.

Once the sauce is thick and boiling, remove a ladleful and slowly pour over the sour cream mixture, whisking to emulsify. Lower heat to a simmer. Pour the warm cream into the pan and stir to combine, cooking until it's warmed but not boiling. Taste for seasoning and adjust salt and pepper, if necessary.

Return steaks to pan until warmed through, about 1 minute. Remove from heat and slice or cut in cubes or strips. Bring them back into the sauce, garnish with the chopped parsley and serve, over noodles or rice.