The bread is cut into thin slices. The butter is mixed with mustard. Grate the cheese and mix with eggs. The skinless sausages are peeled and cut in length and width of two. Plantain slices are coated with the butter, then spread them over 2/3 of the mixture with cheese and eggs and placed two pieces of the skinless sausages, slightly pre-slit 3-4 places. Sandwiches sprinkle with remaining mixture of eggs and cheese, baked in an oven and serve immediately.