Finely dice one onion then heat 2 tablespoons of olive oil in a medium saucepan and fry the onion for 5-7 minutes until it is lightly browned.
Rinse lentils and rice under cold water and allow to drain. Pour into the saucepan and continue stirring for 2-3 minutes. Add water, salt and allspice.
Bring to the boil then reduce temperature and cover. Cook for 1 to 1 1/2 hours checking from time to time that there is enough water in the saucepan. If necessary add a little bit more.
In the meantime, cut the remaining 3 onions into thin rings and fry in 2 tablespoons of olive oil for 15 minutes until golden brown.
Remove the finished lentils from heat and let it stand for 10 minutes then break it up with a fork and mix with the fried onions.