Mushroom roulade (Mushroom puff pastry/ Beef Wellington vegetarian version)

Hello dears, we continue the series of delicious recipes for the holiday table! I propose this mushroom roll that is so full of taste and flavor. If you have vegetarian guests at the table or simply want to have meat-free food on the holiday table, this puff pastry roll is the perfect choice. it is very simple to make and extremely tasty! It's the vegetarian version of the Beef Wellington recipe. As I promised you, I always try to bring the taste of childhood to the table, but also surprise you with all kinds of goodies that I don't think you've tried before. I leave you the filmed recipe here and below I leave you all the details:   You need: 500 g mushrooms (I used 300 g brown champignons and 200 g porcini/wild mushrooms) 200 g of spinach 2-3 cloves of garlic a red onion 2 tablespoons of butter 3 tablespoons of breadcrumbs an egg for greasing a sheet of puff pastry a teaspoon of rosemary salt pepper 3 tablespoons of olive oil 2 tablespoons of balsamic vinegar 3 tablespoons of dry red wine   Clean and chop the onion. We put it to temper in olive oil. Let it simmer for at least 15 minutes so that it becomes sweet and soft. At the end, we add a spoonful of balsamic vinegar on top and leave it until it evaporates. When it's ready, put it aside in a bowl. Cut the mushrooms into slices and put them in the pan in butter to cook. We leave them until...