Peel the sausages from the film, peel the onions and garlic and wash thoroughly.
Cut the peeled sausages in half lengthwise, without cutting all the way through, so that the two halves are connected to each other like a book. Coat the insides of the sausages with mustard, place pickled cucumber cut into thin slices on top, add chopped garlic cloves and chili pepper.
Cut the peeled onion into thin half rings and transfer part of the onion to a jar for pickling sausages. Place stuffed sausages on top of the onions. Layer the sausages and onions. Sprinkle with remaining chopped onion, garlic, chili pepper and pickled cucumbers.
Start preparing the marinade; to do this, pour water into a small saucepan and bring to a boil. Remove the water from the stove, add vinegar, salt, sugar, bay leaf, cloves, allspice, vegetable oil and chili pepper. Cover the saucepan with a lid and let the marinade steep for 5 minutes. Pour the finished marinade into a jar with sausages, close the lid and place in the refrigerator for 3-4 days.
Serve spicy pickled sausages in Czech style as an independent snack or with any side dish.