Wash the tomatoes, carve them crosswise and blanch them over hot. Quench cold and remove the skin. Halve the tomatoes, remove seeds and cut the flesh into fine cubes. Wash the thyme, dab dry and pluck the leaves from the stalks.
Peel and finely chop the garlic. Heat one to two tablespoons of olive oil in a frying pan, add tomatoes, 2/3 of the chopped garlic and thyme. Season with salt and pepper and remove.
Wash the basil, dab dry and, except for a few leaves for garnishing, cut coarsely. Finely chop the basil, 20 grams of pine nuts, remaining garlic and three tablespoons of olive oil in a universal chopper.
Stir in Parmesan and season with salt and pepper. Heat a tablespoon of oil in a frying pan and fry the liver for five minutes while turning. Season with salt and pepper and remove. Let it cool down a bit and cut it into small slices.
Clean the mushrooms and chop all but three of them. Cut the remaining mushrooms into slices. Peel and finely chop the onion. Wash the sage, dab dry and cut into fine strips, except for a few leaves for garnishing.
Heat a tablespoon of oil in a frying pan, fry the mushroom slices in it and take them out. Stir-fry the remaining mushrooms and onions for five minutes. Add sage and season with salt, pepper and a little nutmeg.
Cut bread into twelve slices and sprinkle with the remaining olive oil. Toast slices of bread under the preheated oven grill (or without oil in the toaster and sprinkle afterwards) from both sides.
Cover four slices each with tomatoes, basil pesto or mushrooms. Garnish with pine nuts, mushroom slices, parmesan curls, sage and basil leaves and serve immediately.