Slice the mushrooms into quarters and chop half of the onion while slicing the other half into thin strips.

Heat a pan with olive oil, add the chopped onion, season with a pinch of salt and pepper, and sauté until softened. Let it cool.

Mix the sautéed onion with the meat seasoning ingredients, knead thoroughly, divide into four portions, shape into patties, and flatten slightly in the center.

Heat a pan with oil, cook the patties on medium heat until browned on both sides, then cover the pan and cook on low heat until fully done.

In the same pan, melt butter, add sliced onion and mushrooms, and sauté for 2 minutes.

Add the sauce ingredients to the pan and simmer until thickened.