I make my own triple sec. It’s so much better than anything you can buy. Whenever I have a bunch of oranges I peel them carefully, avoiding taking any of the pith as much as possible. Fill a mason jar and submerge in vodka and put away in a cabinet. Remember to give it a little shake every once in awhile.
After a month strain the vodka out. You can further finely strain or even put through a coffee filter. That’s just a matter of preference and esthetics because you will get sediment. It’s fine, nothing can live in there.
Weigh the finished vodka and add sugar to the ratio of .3 or 30%. So if you have 500ml of vodka add 150g of sugar. Stir til dissolved.
1 Liter finished is 856ml liquid and 260g of sugar