Soak the boletus in lukewarm water for at least an hour.
Remove mushrooms from the soaking water, filter the water, set aside.
Wash the mushrooms a little more under running water and cut them into small pieces if necessary.
Sauté the finely chopped onions and garlic in butter, add the mushrooms and sauté. Deglaze with the white wine, simmer for a short time, add the soaking water and the bouillon paste and allow to dissolve. Add half of the chopped parsley and reduce the sauce to two thirds.
Dissolve the maizena in a little cold water and add to the sauce to set, let it boil gently. Then add the cream and the rest of the parsley, season with salt and pepper.
In between cook the pasta so that it is roughly done with the sauce.
Arrange the pasta in batches on a large white plate, pour some sauce over it and decorate the edge of the plate with the paprika and chives.