Place the shredded carrots in a large mixing bowl. Add salt, sugar (optionally), paprika, cayenne pepper, ground coriander seeds, pressed garlic, black pepper and vinegar. Mix really well and taste. Adjust for salt and vinegar if needed.
Heat oil in a medium size sauce pan over high heat. Carefully add the quartered onions and cook until outer parts of the onions get golden brown. Remove from the heat and discard the onions.
Pour the hot oil very slowly over the carrots while mixing the carrots with a wooden spoon with a long handle to avoid burning hands. Ideally, have one person gently pour the oil while the other person is mixing the salad.
Transfer the shredded carrots into an air tight container and refrigerate. The carrots will be ready in about 6 hours. Will keep refrigerated for up to 2 weeks.