With a sharp vegetable peeler, peel the yellow rind from each of the lemons taking care not to remove the bitter pith (white part). Place the peels in a large gallon size jar with an airtight lid. Pour a liter of grain alcohol or vodka over the lemons. Cover tightly with the air tight lid. Wrap with a dish towel and place in a cool dark area. Shake the jar every day for three weeks to help the peel infuse with the alcohol.
After three weeks: make a simple syrup with the 2 cups of sugar and liter of water. Bring the water to a simmer, add the sugar and stir until the sugar dissolves. Let cool.
Strain the lemon peel from the alcohol over a fine mesh strainer saving the delicious yellow liquid. Pour the simple syrup into the lemon infused alcohol. Funnel into sterilized bottles and seal with a rubber or cork top. Chill for an additional week or place into a freezer.
The Limoncello is ready to drink. Serve directly form the freezer pouring onto small glasses.
This make 4 bottles of Limoncello