Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: see manufacturer). Place tortillas on a baking tray lined with baking paper.
For the sauce, clean and wash spring onions and cut into rings. Peel garlic and chop finely. Mix with tomato paste, strained tomatoes and oregano. Season with salt and pepper. Spread on tortillas.
Spread the salami and olives over it. Sprinkle with cheese and bake in a hot oven on the middle shelf for about 12 minutes.