Marinade for even very tough meats

It isn't hard to cook an expensive cut of meat very tender, however, it gets more difficult to make a tough piece of meat so that it melts on your tongue.

I have a marinade which makes cheaper meats also more tender.

You need:
1 to 2 bottles of no-name coke, pour into a deep bowl. Use the regular coke, not diet coke.
50 ml vinegar
Then add at least 5 cloves or garlic, you don't have to peel them, just press.
3 bay leaves
1 onion, not peeled
1 teaspoon salt, 1 teaspoon pepper

Leave the meat in this marinade for 4-6 hours. Take it out and cook or fry according to the recipe.