Cook the spaghetti in salted water until al dente.
Melt some butter and sauté the onion and chili peppers in it. Now everything should be prepared within 4, max. 5 minutes because the boundaries between soft and hard liver are very fluid and thin. The liver can quickly become uncomfortably gritty.
Add the liver, fry very briefly by stirring constantly. Sear the tomato paste, add the Marsala and let it evaporate a little. Deglaze with half of the wine and coat the liver with it by stirring. When the wine has almost completely evaporated, add the rest and continue stirring. Season with salt, pepper and maybe, depending on your taste, a little sugar. Remove from heat and mix in parsley and oregano.