Mushroom Solyanka

Bring mushrooms to a boil in water and simmer for 30 minutes. Strain the mushrooms, keeping the broth.

Dice the onion and sauté it in butter.

Cut the cucumbers into thin strips, place in a separate pan, pour the pickle brine over them, and braise for 10 minutes.

Mix the tomato paste with water and add it to the onion. Cook for 5 minutes.

Slice the mushrooms and add them to the hot broth. Once it comes back to a boil, add the onion, then immediately add the cucumbers. Bring everything back to a boil and stir in the capers.