Tip in the butter beans and the creme fraiche, stirring so that the creme fraiche melts into the sauce and becomes thick and creamy. Simmer for another 5 - 10 minutes until the beans warm through and you have a thick sauce.
800 g tinned butter beans, 4 tbsp creme fraiche or double cream
Don’t rush the mushrooms: Let the mushrooms brown well, as this enhances their flavor. High heat is key to avoid steaming them. If you have a small pan, consider adding the mushrooms in batches to avoid them releasing lots of moisture and essentially boiling.
Thickening the sauce: The flour helps thicken the sauce, but you can also mash some of the beans into the sauce for an extra creamy texture.
Balancing flavors: The Dijon mustard and balsamic vinegar add brightness to the dish, so don’t skip them! You can always adjust the amounts to suit your taste. A traditional stroganoff will often have some Worcestershire sauce added, but this isn’t vegetarian.