In most Italian supermarkets or groceries, we can buy bottles of 95% proof alcohol, which we use to produce all sorts of infused liqueurs, but mostly limoncello, the famous Sorrento-liqueur made from lemons, also if someone like to add tangerine too.
Every family has its own recipe but more or less they are similar and the difference is in the alcoholic strength due to the amount of water added, while someone like to add more tangerine peels than lemons one.
The following one just is the classic recipe (but take into account that you can use half doses or according with the capacity of the alcohol bottle you buy. In Italy we easily find 1 ltr, 1/2 litr or 75 cl. bottles).
8-10 lemons (the spring harvest when they have the best perfume and still unripe);
1 ltr 95% proof alcohol (often we also find 75 centiliters bottle that someone prefer to get a limoncello with less alcohol content);
1 ltr water;
1 kg sugar.
Peel the lemons roughly and put the peel into the liter of alcohol; you can use any container but capped up. (The inside of the fruit can be used for other purposes if you need it).
Leave for a week (a day more or a day less gets no importance but leave it until peels fade and become hard) so that the flavors from the peel infuse into the liquid that step by step will become yellow.
When ready, boil the water and dissolve the sugar in it.
Wait till this mixture is cool.
Meanwhile, removed the lemon peels from alcohol.
Then add the mixture to the alcohol blending with care.
Decant (better using a filter but even a cotton wool is good) into smaller bottles to cork up and store.
Serve chilled straight from the freezer.
We Italians usually drink it after a good meal.
Since more than 2 ltr of liqueur could be too much for you, instead to utilize the whole bottle of alcohol you could use the half dose of any ingredient and in this case also check if the alcoholic strength meet your liking. If okay you must repeat the procedure to get other liqueur otherwise, when preparing the new portion, you could use more water (and even more or less sugar according to your taste).