Crumble yeast into a large enough bowl, stir with a quarter of lukewarm water until smooth. Knead with flour and salt to a smooth dough. Leave in a warm place with the lid closed for about 30 minutes. Remove the stalks from the tomatoes, put them briefly into boiling water and rinse with cold water. Cut tomatoes in half, remove seeds and cut into small cubes. Rinse, clean and chop the onions. Chop the peppers. Chop basil not too small. Cut peppers and king prawns into small cubes. Drain mussels, mix with pepperoni, tomatoes, green onions, peppers and basil. Season heartily with salt, pepper and paprika powder. Sprinkle a work surface with a tiny bit of flour. Divide dough into 8 pieces and roll out oval patties on the floured work surface. Oil a baking sheet. Place dough patties on the baking sheet and top with the tomato frutti di mare mixture, sprinkle with the pizza cheese mixture. When topping, leave a border of about 1 1/2 cm free. Brush a little olive oil over the top. Fold the edges about 1 cm inwards and bake in the oven heated to 200 degrees for about 25 minutes.