Here's how to make a simple alcohol base that can be used for distillation or for flavourings to be added.
Without being distilled you can get this up to approx 20% ABV.
This has many names the world over, but is normally referred to as Kiljuin in Finland, or more popularly, just Sugar Wine.
So here's how to make it.
Tip: Brewing sugar is the best to use as it does not impart any flavour. Supermarket sugar can leave a taint.
1 gallon boiling water
1.5kg brewing sugar
1 sachet of High Alcohol yeast
1 tsp Yeast Nutrient
Into a bucket add the sugar and pour on the boiling water.
Stir to dissolve all the sugar, cover and leave it to cool to 20°C.
Then add your yeast. Cover and place in a warm cupboard (approx 20°C) for 1 week.
Then transfer to a demijohn with an airlock, put back in your warm cupboard and and leave to fully ferment, approx 2 more weeks.
If you wish it to be as strong as possible, you can "feed" the wine. This simply means adding more sugar to the wine. Add a couple of teaspoons of sugar at a time and you should see an instant reaction with lots of bubbles. You can keep adding a couple of teaspoons every few days. Each time you add the sugar, make sure there is a reaction. If no reaction occours, then you have reached the limits of the yeast you are using and so you have reached the maximum ABV for your brew. Adding more sugar now will only make the wine sweeter and more licquor like.
Once the fermentation has finished, rack into a clean sterilised demijohn and leave to clear. This can take up to 4 weeks.
This is best filtered to make sure no sediment remains.
Bottle and drink whenever you want. It can be drank young, or you can age it. Drink it neat, add cordial or licquor flavourings.
It's as simple as that.